It is sad because it was such a well designed community. But its lessons live on.

Nah. It launched well, but sorely needed a BDFL. Almost without fail, services that delegate moderation duties to users are ruined. Inevitably, well-meaning people form councils and boards, and then those get taken over by people with nothing but time on their hands. It's the same thing that happens with school boards and HOAs: the last people you want running them are the ones that have the time and the drive to actually want to be in charge of them.

It was an AMAZING community... right up until it wasn't. I cut my teeth on trying to answer questions and learned how much I didn't know when other people's answers were better than mine. Literally made a career out of what I learned there, and I thoroughly enjoyed welcoming people to SO and encouraging new coders to keep learning. But then dang, the question purists and eager close-every-question jocks came to dominate the platform and made it no fun to ask or answer. Even if AI was never a thing, the change in culture probably would have opened the doors to a competitor.

Everything is cyclical. Maybe they come back when AI gets heavily regulated or pay gated. Who knows

does well designed mean rotten and pointlessly hostile

StackOverflow helped build the LLMs that replaced it.

it was as well designed as the nipples on a man