As someone who only ever browsed all, I see no difference.

The OC to porn ratio has shifted in favor of porn.

I lost all patience with low effort posts. I try to call out anyone asking easily google-able questions or clear karma baiting. It took a couple days of this to realize I needed take a long break from it. I'm debating keeping my account solely to get my karma up a bit more and trying to sell it, not sure yet.

Probably yes, many of people from subreddits I followed left

For a bunch of the subs I frequented the mods just left. Some of those died, some are being taken over by right-wing extremists, some are still chugging along.