I’ve recently started wondering how many people are here because they’re too toxic for regular social media rather than because they want to be here.

Dude yes, I've been thinking the same thing. I worry that users curious to leave reddit are going to go to a big instance, see concentrated worst-parts-of-reddit, and decide it's not for them.

In theory, decentralization enables freedom from the average user being forced to put up with toxicity. But we don't really have that (yet) until the ratio of jerk to non-jerk improves.