RMS is unemployable at this point. He is also 66, so he could just retire as an option.
But ultimately RMS's positon was one of political, not technical, leadership. With no more supporters, the FSF rejected him. Without the FSF, what purpose could he serve at his job?
That doesn't imply any institution of higher learning or software advocacy organization needs to grant him their imprimatur to do it.
He could try to rebuild his career, but he is 66 so unlikely he will try.
Isn’t he basically a speaker and advocate nowadays? That career is unlikely to be very successful now that all major organizations dumped him and he has fake news headlines saying he defended Epstein following him everywhere (backed up by apparently two decades of known antisocial personal behavior).
He doesn’t exactly sound like the kind of person you’d hire to work as a normal developer nor would that comport with his strange ethics of refusing to use any non-Free software.