There is a lot of noise about the inadequacy of Twitter, that it is stagnant, lacks innovation and does nothing that actually improves life. In fact, there seem to be an increasing number of people leaving for just that reason. Here's another one. Lindy West has left because it is "unusable for anyone but trolls, robots and dictators".
Trump uses his Twitter account to set hate mobs on private citizens, attempt to silence journalists who write unfavourably about him, lie to the American people and bulldoze complex diplomatic relationships with other world powers. I quit Twitter because it feels unconscionable to be a part of it – to generate revenue for it, participate in its profoundly broken culture and lend my name to its legitimacy. Twitter is home to a wealth of fantastic anti-Trump organising, as well, but I’m personally weary of feeling hostage to a platform that has treated me and the people I care about so poorly. We can do good work elsewhere.