I personally didn't use it so much (meaning: Writing content) because it always felt a bit over engineered. From what I remember the only possible entry point is writing questions that get up voted. Not allowed to even write comments, vote and of course not allowed to answer questions. Maybe that's not correct but that has always been my impression.
In general stack exchange seems to be a great platform. I think "it's dying" has an unfortunate connotation. It's not like content just vanishes, just the amount of new stuff is shrinking.
I stopped contributing when the question quality fell of a cliff. Existing contributors got annoyed by the low effort questions, new users got annoyed because their questions got immediately closed, it was no longer fun. There were a lot of discussions on meta how to handle the situation but I just left.
So admittedly things might have changed again, I do not really know much about the development in the last ten or so years.
If you're logged out it's just a list, but if you're logged in it'll grey out and put a checkmark next to the ones you have.
But yes, AI put the nail in its coffin. Sadly, ironically, AI trained off it. I mean AI quite literally stole from Stackoverflow and others and somehow got away with it.
That's why I don't really admire people like Sam Altman or the whack job doomer at Anthropic whatever his name is. They're crooks.
So makes sense that SO like users will use AI, not to mention they get the benefit of avoiding the neurotic moderator community at SO.