If they are storing a this data anyway to make the thing work (so you can go and un-upvote the thing you upvoted five years ago), how is "privacy" reduced if they also have the as system decide to show you an ad because people who upvoted that thing tend to click on the ad?
No new people or businesses are being given any new information bout anyone. Is it because what used to be a passive database is now starting to think, and your privacy is infringed because the system itself is now looking at you when you didn't expect it to?
Right now.
But everybody is also moving into their castle. Many for free.
They are not allowed to let people do that unless they have an argument that, somehow, this makes money for the owners of Cloudflare. Maybe that's in the form of good publicity. Maybe they're hoping to set up some tollbooths at the castle gate, once enough people are inside and the other options have withered for lack of customers.