With Democrat control of the House such a bill would have no chance of becoming law. Yehuda points out that bills are sometimes introduced for show, even if they have no chance of becoming law, to demonstrate a party's commitment to making something happen, or so that opponents are forced to vote for or against something that can be used against them later. Why are they not doing this?
The main reason is that the promise to the electorate made by President Trump was to "repeal Obamacare and replace it with something better". The bill that failed in the Senate did repeal Obamacare, but did not replace it with anything (better or not). That was one main reason it failed. There was no replacement because Republicans could not agree on what a 'better" replacement would look like. Many thought that there should be no replacement, but this would deprive many potential Republican voters of affordable healthcare, and remove popular reforms such as being able to get insurance for pre-existing conditions. Democrats are widely associated with the ACA, and so are unlikely to suffer by being forced to vote to keep it.
The likely effect of such a vote (even if not passed) would be to expose divisions in the Republican party over what healthcare should look like, to give opponents ammunition as Republicans voted to remove popular policies, and to draw attention to the fact that Republicans, while promising to "replace Obamacare with something better" are actually voting to simply remove it.