Many people online have a tract they feel the need to bring out at every opportunity they can. The most common one is politics, and in the past, it was religion. That’s why internet fora would always ban those topics, except in separate parts specifically for those things, because if you don’t deal with them somehow, they will overtake everything. The big social media sites didn’t feel the need to have safeguards against these things*, and are being shitted up for it.
*Reddit is an exception. They had a wonderful idea that each topic of discussion could have its own separate subreddit, so people could find a place to post anything, rather than posting anything in one place. Lack of moderation has caused this idea to fail in many subreddits, but since Reddit put the job of moderation in the hands of its users, I don’t blade Reddit for this failure. At least, until they did start moderating, in a very partisan way, just like the other social media websites. Yay.