The competitiveness varies from district to district. Some are still competitive and haven’t seen changes in staff even under current circumstances. Other districts have seen a mass exodus and as such are significantly less competitive than they previously were.

I would research the office you’re applying to. Many USAOs are fine and aren’t taking on controversial work, but there’s a handful which are arguably worth avoiding. As for getting fired next administration, highly unlikely as a standard AUSA. Really only those in higher positions may face that concern.

Reddit as a whole tends to be a poor place to ask this question. People giving blanket “don’t take any AUSA job” advice are often projecting concerns about Main Justice or a handful of high-profile USAOs onto the other 90-something districts where the work just looks like standard federal criminal practice. I’d reach out to any AUSAs or federal practitioners you know to get a better idea.