RFK is, in my view, the nominee most likely to get pushback from the Senate. I could see them swallowing all the other appointments but drawing the line there.
We just went through a fucking pandemic. If they create another one because of lack of vaccination, they will lose their jobs permanently. I cannot imagine anything that would be worse for the GOP brand than ushering in a huge pandemic of childhood illnesses. Maybe I'm still being too optimistic. Maybe I cannot understand the depravity.
For what it's worth, I suspect RFK's impact would be fairly mild. I don't think there are any decisions committed to the Secretary's discretion, which means that everything would be subject to APA procedures -- meaning that the policies would have be supported by substantial evidence. Obviously there is no such evidence and any attempt to weaken vaccination would likely be struck in court basically immediately.
Whether SCOTUS would agree is of course always the open question, but I continue to think that SCOTUS has no interest in the anti-vaxx shit, which is a distraction from the real business of that majority. I don't think they will destroy HHS over vaccine paranoia. But who knows.