There's a CloudFlare engineer who posts prolifically here on HN; he's denied that they sell data of any kind numerous times. I think it's safe to take them at their word without proof otherwise? https://news.ycombinator.com/item?id=12830120
There is nothing particularly dangerous about accepting claims from strangers on the internet at face value. I don't use their service, so I'm not going to be harmed by anything he says if he is lying or if he is telling the truth. If I decide later to use their service or if he says something that seems false or misleading when taken at face value, I can adjust my level of skepticism accordingly.
Still, I would assume by signing their ToS you are agreeing to some hefty terms.
Equating John Graham-Cumming to a random engineer has, on HN at least, about the same weight as equating PG to a financially succesful blogger. The statement is factually accurate but deliberately ignores the wider context.
Yes - I'm painfully aware that I just used the halo effect as a weapon. But the fact is that provenance and pedigree matter.