We're both necessarily speculating here, so I'll counter by suggesting that an enormous proportion of Twitter users don't actually care whether or not they're u

We're both necessarily speculating here, so I'll counter by suggesting that an enormous proportion of Twitter users don't actually care whether or not they're using Twitter, they just care that the content they want to consume and the people they want to follow are on Twitter. They can't be "using Reddit or Discord if they want to be", because that's not where the community already is. Solving the collective action problem to overcome this inertia is hard, but easier in tumultuous times like these.