Mastodon could flop, Mastodon could be bigger than Twitter, we don't know. But you damn sure aint gone know if you don't try it.
Most of this is coming from people just not wanting to lose their huge following on Twitter.
You're used to having 10,000+ followers and you don't want to give that up.
And yes I also understand a lot of our friends are on Twitter and there's a good chance they won't even attempt Mastodon either.