It’s not fishy at all. everything that’s happened has caused these communities to grow exponentially to unprecedented levels. tripling or quadrupling in size. It’s like asking why a house party of a dozen people doesn’t get raided by the cops and a party of hundreds does.
Of all actors, platforms like Discord and Facebook should understand that such an influx makes it quite hard to moderate well. And that there is also a risk of adversarial actors infiltrating the groups. If they had any interest in the well-being of said communities, they would show some understanding of this challenge. At the very least wait a few days until things have shaken out. But no, straight to the ban hammer, with no dialogue.