I think Twitter will die but I don't exactly hope that it will.
The best thing that could come out of this is that Mastodon gets critical mass such that it can survive on its own. We don't have any popular services besides email which are decentralized anymore.
Mastodon is more complicated than Twitter because you have to "pick a server" and that's true but at the end of the day all that matters is where the people are.
If enough content generating posters will just make the shift at once then this thing can be self-sustaining...even if it is more complicated.
Twitter was more complicated than not using Twitter and people still started using it. This is perenially true for all new things.
Anyway, it's late and I'm tired.
Long live microblogging.