I mean... not even, right? A "livelihood" is one's ability to make money in their career, not specific to an individual job. Surely these highly qualified people will find work elsewhere.
So it's really not worth getting dramatic about. It's sad, but such is life. I wish the best of luck to these folks, but I doubt they're in mourning. I'm sure the YC leadership is helping them figure out next steps as we speak.
Things like this are almost always traumatic regardless. We wrap ourselves and our identity in our jobs, especially ambitious and successful and highly qualified people. While objectively you’re right, it is still unnerving and unpleasant to have to find a new job and learn your contribution and value to the company was worth less than others. It’s also not the best job market for tech focused folk. I think it’s ok to feel sympathy for someone laid off.