Again, I'm not seeing an unambiguous TOS violation here. They have some catch-all stuff about creating an undue burden and an even broader clause saying, essentially they can drop any customer without cause. I have no doubt Cloudflare is legally in the clear, but when I read about something like this, I think I wouldn't set anything important up with Cloudflare as a critical part of its infrastructure.
Of course, the author could be leaving out a bunch of context to make himself look good.