One current model of what's happened/happening, is the US system of politics is broken (first-past-the-post voting in states, 2 seats per state, two party, pola

One current model of what's happened/happening, is the US system of politics is broken (first-past-the-post voting in states, 2 seats per state, two party, polarization ... and now on top of that the drawback of the separately elected president is that now the Executive and the Legislation was in a deadlock), so the private sector stepped in its usual awkward way. (FB/Tw/YT profited from hosting recruiting content, they did some minor moderation to calm advertisers, but now real people realized that they have the capacity, right and maybe even moral duty to do something with the problem they helped to create, so reverse course, full throttle backward, bam-bam, ban, ban.) It's not about illegal content. It's about politics and ethics. (And private companies can choose to do or not do business with whomever they want - except a few protected things. But there's a gay wedding cake somewhere too in this. Free association and free speech. Ethically it's hard to coerce anyone to say or not say something, and to host or not host some content.) Furthermore, there's the power imbalance aspect. Twitter banning SciHub is probably Twitter abusing its power, Twitter banning Trump is less likely an abuse. (Though there very well could be and are exceptions.)