Beyond what pyre noted about a time limit, the kind of people who have those highly-important skills and knowledge tend to be the kind of people who are looking for new accomplishments.

I'd expect some would go somewhere different (e.g. leave Intel to work at AWS learning more deeply about what people do with those chips before jumping back), be grossly underpaid helping their favorite charity, take classes/do research, etc.

It's not indefinite. There are already non-compete contracts that exist like this, and there doesn't seem to be a problem with people purposely using them as paid vacation.

You get golf on the beach when you leave no matter how long you stay at Intel (in this hypothetical scenario). Leaving now doesn't get you more golf on the beach.