There are cabinet heads and undersecretaries and deputies that get appointed. Below them are the career people who really run the departments. I think it would be fine for those people to decide that the career management should go. But below that, nah. Unless they’re not doing the job their manager tells them to do, they’d be immune from administration changes.
If they cannot be fired for watching porn on government computers all day, what can they be fired for? I admit I do not have a solution, but not acknowledging that bureaucratic DC is biased for democrat policies and has a built in bias against republican priorities is to overlook the obvious.