It's the early signs like this that needs the rest of the community to come out against the right hard and relentlessly. Just name and shame until they go away. Allowing them to keep spouting bullshit just gets you a slow roll into fascism. I hope they can accomplish it.
I mean, I don't want to sound like an old fogie or anything but when I was a kid when people would say stupid shit we would just ignore them and tell each other to walk on the other side of the street around them.
We would not listen for the crazy words that crazy people say and then run around telling them to everyone else as if there were any weight or value to those words.
I'm sure if you look hard enough you can find some crazy person saying some crazy thing about any topic you can imagine. Why are we taking those crazy people and putting them up on a planetary podium and putting a microphone in front of them?
The people who are giving the crazy people megaphones are bad people and should be stopped.
The problem as I see it is that those crazy people discovered the internet, and met the other crazies that reinforced the stupid stuff they believed. And when enough of them got together, people started to notice and someone was like, "I can make money off this by making them interact with non-crazies." The first probably was Facebook, but after others saw how profitable it was, they decided to have their own slice of the pie, which in turn made those fringe groups more noticeable.