Buddy had one. Second-hand, it seemed like a tremendous pain in the ass, didn’t allow him to do most things, and in the end it seemed a moot point. The radios are all closed source/proprietary, it connects to closed source/proprietary/corporate-controlled towers, and you’re sending data to people running totally insecure devices. Ultimately his use case was to just establish a VPN connection to his home computer and route everything through that.
I can see getting into a Linux phone for the interest of the operating system and trying to push the technology, but if it’s a security/privacy issue, I think you’re much better off either using a dumbphone or a burner.
Mastodon isn’t really about the “celebrity” follow how twitter was, it’s more about finding your own tribe of weirdos. I second (third?) the idea of following hashtags, and then checking out those accounts that post to those tags.
The other thing I’d like to mention is the people I see happiest on Mastodon have all migrated servers at least once. Get an account on one of the big main servers, explore, then move to a small instance that suits your interests and has people you like. That makes for a much more useful and entertaining local feed. Don’t feel it needs to be a 100% match, it’s more about the people (it’s about the cones ).