I have multiple accounts on Mastodon, kbin, Lemmy, Misskey and Pixelfed. I originally signed up to different communities to get a feel for what worked for me. I'm glad I did because one was sold (mastodon.cloud) to a shady spam company, and my favorite Mastodon instance that I settled on had an admin hissyfit and shut down because he didn't own any big boy pants. And another instance suddenly became a csam farm and I deleted that crap real fast.
I still visit a few local communities to see how they have developed, some better than others. Some are just people moaning about everything they can post about, just like twitter is. So annoying.
I personally find that I have more fun on kbin and I use Mastodon for news and keeping up with hashtag follows. I really hope in the future that kbin gets more tools like Mastodon with following hashtags, bookmarks and a filtering system like they do. It's really nice to be able to mute and block other people easily.