I think it's reasonable to expect an astronaut to report to work on the day of a launch regardless of personal circumstances. Also a soldier can't go AWOL in the middle of a mission to see his family. Same with a surgeon in the middle of a surgery. Those are pretty much the only cases I can think of.

I get the sense that, amusingly, Elon Musk sees himself and his company as that important.

Completely agree! Nobody should be shamed because he/she prioritizes things differently. As long as people accomplish the job agreed upon, it should not matter that some people are not OK with never seeing their family.