TL;DR: Without going into the definition of "genocide" or a moral debate about China's dealings with Uighurs, I'm going to agree with @PhillS in saying that there's a good chance the labelling at this late hour is just another problem lobbed at the Biden/Harris administration. The timing is suspicious, since Pompeo put sanctions in place in July. Even if it wasn't intended that way by Pompeo, it's likely he felt he had no other choice to avoid the wrath of Trump.
Long Form
Is the labeling of "genocide" just an empty gesture?
Generally no, but in this case, it really is. With Pompeo not having to worry about any repercussions from Trump, he is free to say whatever he wants. I haven't been following this situation at all, but evidently this problem has been happening for years in China, yet a "final decision" is only made as Trump's administration is packing up to leave? This is totally an empty move by an outgoing regime.
Odds are that Biden and Harris will have to keep the labelling, regardless if they were going to label it that way anyway, so they have to immediately have to deal with it instead of on their own time, delaying some other things they were likely going to do. This makes it not an empty gesture, but only if it's followed through.
As an aside, this is just another thing Trump can say he made a decision about without having to take any responsibility for the outcome.
From The Hill article in the Question:
“We applaud the Trump administration for recognizing the scope and depth of these atrocities," the commission said in a statement.
One could say this is only just another Republican tactic to hamper the incoming Democrat administration, but that would make assumptions on intent that I'm not sure we have enough information to make a decision on. That information may come out in the next couple days or weeks, if those kinds of answers are forthcoming at all. It seems as if Pompeo has been looking into this for around a month, so it might just be a case of him throwing his hands into the air, while not longer having them tied by Trump, and making the decision that yes, it is genocide.
U.S. Secretary of State Mike Pompeo has ordered a review to determine whether China’s repression of ethnic Uighurs in Xinjiang amounts to genocide, several officials and people familiar with the matter said, raising expectations that America’s top diplomat may charge China with committing genocide before he leaves office next month.
https://www.uyghurcongress.org/en/pompeo-weighs-genocide-designation-for-china/
Pompeo was even invited to take a tour in July, but then waited until December to order a review?
A Chinese foreign ministry spokesperson has invited Secretary of State Mike Pompeo to visit the western region of Xinjiang, following the latest round of U.S. sanctions on Chinese officials accused of involvement in the oppression of Muslim minority groups in the restive province.
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Former inmates have described a wide range of human rights abuses in the camps taking place in inhumane conditions. Reporters allowed into supposed detention camps are shown carefully choreographed examples of daily life there, framing the centers as vocational and voluntary facilities designed to improve the lives of Xinjiang residents.
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This includes those involved in the suppression of Xinjiang. Last week, Secretary of State Mike Pompeo announced visa restrictions on a group of officials he accused of overseeing "forced labor, arbitrary mass detention, and forced population control, and attempts to erase their culture and Muslim faith" in the province.
"The United States is taking action today against the horrific and systematic abuses in Xinjiang and calls on all nations who share our concerns about the CCP's attacks on human rights and fundamental freedoms to join us in condemning this behavior," Pompeo said.
https://www.newsweek.com/china-invites-mike-pompeo-visit-xinjiang-no-rights-abuses-1518294
Mike Pompeo also warned US companies to avoid working with certain Chinese companies, again in July, so why wait until now to make a final decision about what to call the known civil/human rights violations?
"The advisory will make businesses aware of the potential exposure in their supply chains to entities that engage in human rights abuses in Xinjiang — or elsewhere in China — and the associated reputational, economic, and legal risks of such involvement," Secretary of State Mike Pompeo said in a statement.
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The Commerce Department previously has put 37 Chinese enterprises on its "Entity List" for engaging in or enabling human rights abuses in Xinjiang, a move that further restricts their access to U.S. goods and technology through much tougher licensing requirements.
https://www.politico.com/news/2020/07/01/uighur-china-us-companies-346974
The Chinese Connection
You might wonder why I think Pompeo is wary of Trump's reaction to this ruling when Trump started a trade war with China. The simple fact is that Trump has lots of Chinese business and financial connections to his personal businesses. From a personal bank account, but under the name of his businesses:
And it turns out that China is one of only three foreign nations — the others are Britain and Ireland — where Mr. Trump maintains a bank account, according to an analysis of the president’s tax records, which were obtained by The New York Times. The foreign accounts do not show up on Mr. Trump’s public financial disclosures, where he must list personal assets, because they are held under corporate names. The identities of the financial institutions are not clear.
https://www.nytimes.com/2020/10/20/us/trump-taxes-china.html
To making money here in the US off the Chinese government:
President Donald Trump, who declared “I don’t make money from China” in Thursday night’s presidential debate, has in fact collected millions of dollars from government-owned entities in China since he took office. Forbes estimates that at least $5.4 million has flowed into the president’s business from a lease agreement involving a state-owned bank in Trump Tower.
https://www.forbes.com/sites/danalexander/2020/10/23/forbes-estimates-china-paid-trump-at-least-54-million-since-he-took-office-via-mysterious-trump-tower-lease/?sh=4b9ce248ed11
To trying to file for trademarks in China for years and succeed only after he was elected:
Indeed, Trump had tried for more than a decade to register trademarks in China to provide “construction-information,” essentially real estate agent, services in that country, only to be met with a series of unsuccessful rulings and appeals. Since 2005, Trump has applied for at least 130 trademarks in China, all of which—until recently—were met with zero success.
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And then, lo and behold, China’s approval of one of Trump’s trademark applications became official—coincidentally only a few days after Trump reversed his previous position and endorsed the “one China” policy. This policy effectively recognizes the People’s Republic of China as the legitimate government of the mainland territory while allowing the U.S. government to have unofficial relations with Taiwan, governed by the Republic of China. In March 2017, China granted preliminary approval for 38 additional Trump trademarks, applications for which had been submitted in April 2016. While there are conflicting views about whether the process and timing of Trump’s recent trademark approvals are suspect, the reality of the matter is that in China, every administrative or judicial decision is a political one based on the government’s preferences and priorities; courts in China are not independent, but rather they report directly to the CPC. Also of note here is the fact that foreign companies have historically struggled to get equal treatment under Chinese law, so decisions in favor of a foreign company are striking. It is hard to avoid the appearance that China was giving Trump the trademarks in exchange for a direct shift in policy. As another Atlantic article points out: “Each subsequent ruling in his favor will serve to remind Trump of the personal profits he could reap by improving his own personal relations with China, even if doing so leaves the American people worse off.”
https://www.americanprogress.org/issues/security/news/2017/06/14/433915/trumps-conflicts-interest-china/
Donald isn't the only Trump with ties to China. His daughter, Ivanka, does quite a bit of business there, too, including getting trademarks due to Donald's election and policy decisions.
China last month granted initial approval for 16 new trademarks for the fashion brand of U.S. President Donald Trump’s daughter and adviser Ivanka, including voting machines, a search of official records on Tuesday showed.
Ivanka announced in July she was shutting her fashion line to focus on her role as an informal White House adviser, where she is working on advancing working women.
Since Trump’s surprise November 2016 election, his family has faced criticism that its portfolio of real estate and consumer goods businesses, which lean heavily on the Trump name, conflicts with its Washington roles.
https://www.reuters.com/article/us-china-usa-ivanka/china-grants-more-trademark-approvals-for-ivanka-trump-firm-including-voting-machines-idUSKCN1NB0TL
She has supposedly shuttered her business interests, but some trademarks are in effect until 2028, so she could restart her interests now that he's left office. And she continues to get trademark approvals even with the businesses being defunct.
...On Sunday, the Chinese government awarded Ivanka’s now-defunct company four new trademarks (including for wedding dresses, sunglasses, and, um, child-care centers), in addition to a fifth that applies to art valuation services and charitable fundraising that was approved on January 6. The timing is terribly convenient—coming just as President Trump has begun engaging in negotiations with China amid the ongoing trade war.
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So, what do the new trademarks even mean to Ivanka’s defunct company? “Despite shutting down, Ivanka Trump’s brand will continue to seek new trademarks, according to public reports. This leaves open the possibility that she could resume her business after leaving her role in the White House,” Citizens for Responsibility and Ethics in Washington (CREW) wrote after Ivanka was awarded the trademarks in October. “She retains ownership over all of her existing trademarks, and many of her trademarks will remain active as late as 2028”—long after her welcome in the Oval Office is officially worn out.
https://www.vogue.com/article/ivanka-trump-china-business-trademarks
If I cared to dive deeper, I could probably pull up other Trump family members that have similarly deep ties to China.
Add in Trump's general penchant for making snap decisions, if he wanted this labelled as "genocide", it would likely have been called that almost immediately, regardless of a review or investigation.
Conclusion
The timing seem to be highly suspicious. Mike Pompeo knew months ago what was going on, yet didn't start an investigation/review until December? That sounds like he saw "the writing on the wall" of Trump's end of Office and took a chance he didn't otherwise feel comfortable making. Whether that's an intentional problem created or not and whether it was intended by Pompeo or Trump will be hard, if not impossible, to decide officially.
Regardless, it's an empty gesture by the outgoing Trump administration, since they have no stake in how it's handled, even if Pompeo didn't intend it to be this way. How Biden and Harris handle it remains to be seen and will determine if it remains an empty gesture.
