All the people I cared about left. Most of the replies of anyone with a larger profile were getting filled up by rubbish.

But I'm sure there are still some bubbles of decent content. It was definitely no longer worth being on there for me though.

Some of the people I cared about left earlier in the Mastodon exodus but when I occasionally check up on them many have just stopped posting there too. It's not really any different from blogs stopping or at least updating very rarely. It happens on Twitter too, people I care about are still there and others have just faded out and gone nowhere. But overall it's not so bad, especially when I stick to the "Following" tab, but the "For You" tab does sometimes surface new interesting people as well and does pretty well at also being a feed for art or photography I like without having to follow specific people. (Of course I have many complaints. Perhaps the biggest is that I never used to use the block feature, but now use it routinely because the "not interested in this post" signal seems to do nothing as far as showing posts from an account less frequently. Then there's the endless waves of bots/bluecheck engagement farmers/etc that get a block if I find them in replies to people I care about and want to make sure I don't see them again in future replies.)