My only issue with Mastodon is the network effect.
There are many accounts I follow on Twitter, relatively popular accounts not friends with 5 followers, that aren’t on Mastodon.
So I’m missing a bunch of what I had. I found new things too, which is great. But it’s still never going to be a 1:1 replacement.
My main entry point to Twitter is their search box (I’m basically a read-only user). Mastodon seems to be resisting multi-instance searching and that makes it more cumbersome for me to use.
If Mastodon isn’t interested in this functionality, it would be cool to see Google add a “mastodon:” search operator that works like their “site:” operator.
What exactly leads you to believe it's not a good replacement, especially considering you haven't tried it?