> There is this trope of the "genius asshole" who is too valuable to lose. I suspect that in a lot of cases these people are too valuable precisely because they drive away other contributors that would otherwise lead to a more healthy project.

I have seen this many a time.

It's quite hard to watch someone tear themselves apart, even if it is just the internet. The emotional burden of it gets a bit too much, and walking away seems like the best option.