I feel like you're criticising just for the sake of it.
Firstly, this post is signed by Adam D'Angelo, the CEO and co-founder. If you had opened the link you wouldn't even have had to scroll down, it's literally on the second line, right after the headline. So clearly Quora doesn't do what you've accused them of doing.
Secondly, what good does crucifying one person do? I'm sure if they had written it such that one person was responsible for everything, a similar comment would have been written - "why make one person the scapegoat? The entire team should take responsibility!!"
I don't know anything about your experience working in software, but when there's a fuck up like this, it doesn't do any good to pin the blame on one person. You figure out where your systems failed, and fix the system after conducting a blame free review. If you start pointing fingers within the team, you'll never get anything fixed.