This isn't about "supporting" someone's views. This is about simply allowing one to speak. Otherwise Google should be held liable for every single illegal thing that happens on their platform (and there are ton of those).
I don’t think Cloudflare is trying to claim liability (that would be a bad move on their part), but just that they want no part of that kind of behavior. They don’t want to take money from or enable that kind of behavior in any way.
