Does the United States Senate actually take the time to interview low level nominees like nominees for low military general ranks (Brig. General) or really specific roles that require senate confirmation (like the Assistant Secretary of Health and Human Services for public affairs?) or is it just kinda a rubber stamp for lower nominees that require their approval?
Approximately 4,000 civilian and 65,000 military nominations are submitted to the Senate during each two-year session of Congress. The vast majority are routinely confirmed, while a very small but sometimes highly visible number fail to receive action.
Note the Senate does not interview minor nominees, and didn't at all historically:
Not until the middle of the twentieth century, however, did those committees routinely require nominees for major positions to appear in person.
What the Senate seems to rely most heavily on, especially for military nominees, is to require rigorous nomination bundles that contain relevant information, including adverse information, and sometimes alleged adverse information. Note the trend in Congressional Review article is more Senatorial scrutiny of some military officers.
Since the early 1990s, the Senate has become increasingly vigilant in examining senior military officer misconduct and ensuring that the nominees they confirm meet the highest standard of accountability. During the mid-1990s, numerous hearings and debates ensued about the suitability for promotion of many senior military officers.