This is sadly a bit of a problem with most Twitter alternatives right now; many more niche communities haven't moved over (or have only chosen to go to one of them), so there's a good chance you won't find content you're interested in. Mastodon seems to have more of the tech crowd from what I can tell, but even then it's maybe 1% of the audience you might have had on Twitter.
They aren't going to move over; the reddit/twitter model of 'crosspollination' is fundamentally flawed - if trolls can just stroll over from their little trollzone at any time they will do so and every conversation will get derailed with politics/gender/whatever gets the most engagement; character assassination will be the dominant paradigm.
Silos are the answer. Open to all but topic focussed and with no cross-referencable userhistory. Or 100% anonymity with no userhistory i.e. futaba type message boards.
