The moderation definitely got kind of nasty in the last 5 years or so. To the point where you would feel unwelcome for asking a question you had already researched, and felt was perfectly sound to ask.
However, that didn't stop millions of people from asking questions every day, it just felt kinda shitty to those of us who spent more time answering, when we actually needed to ask one on a topic we were lacking in. (Speaking as someone who never moderated).
My feeling was always that the super mods were people who had too much time on their hands... and the site would've been better without them (speaking in the past tense, now). But I don't think that's what killed it. LLMs scraping all its content and recycling it into bite-sized Gemini or GPT answers - that's what killed it.