I personally have used Threads, it’s not bad, privacy is bad but I would love to be able to message people from Mastodon to Threads users but I’m unsure when they are adding it to there system, tbh seems like they never will as they just want to collect more data.
Although people are against it, I feel like Threads on the fediverse would bring some more interest and traffic to the fediverse, and mean even if you just use Mastodon/kbin/etc you can eventually also benefit from more official accounts being accessible.