I think its a common misconception that YC primarily invests in 20-somethings eating ramen and dreaming big. Lots of YC founders have kids and stuff. This was true when I went through in YC in 2011 (interestingly first batch that got $250k from Yuri Milner) and doubly true when I just went through in 2021.

I'm skeptical the goal of this is to encourage high salaried people to start companies though, it's probably just to give people extended runway.