I never managed to get into mastodon because mastodon isn't a single space. It's a bunch of separate, linked spaces. Which server you're on matters a lot, and I never found one that really had the vibe I was looking for.
Bluesky, though, is one big pool. There's no seam between servers. The experience is much nicer.
Also, bluesky caught on among my peers in a way that mastodon never did, which was always going to be the deciding factor. I imagine not having to "choose a server" was a big part of that.
> There's no seam between servers.
This is false, if we're to believe it's possible to exist outside the moderation control of Bluesky corp.
It's also false today while everyone is still on the same "instance" - e.g. ICE joining Bluesky and being verified is making waves... apparently being _that_ is not enough to violate Big Blue's community guidelines.