There was a Star Trek episode where Kirk and Spock visit a world that has undergone a fascist revolution.

The leader that started this resolution died some time ago. To keep the stability, the handlers keep the leader's body in a freezer and occasionally put in front of the TV camera. The leader uses tapes of previous speeches. The leader's mouth is in front of a big microphone, so we can't see that his lips are not moving.

The people are happy the leader is still in charge. The handlers are running the show.

I don't see any 25th Amendment happening. AI can do wonderful things these days, even hide the death of Trump.