I took a second look at ad blockers on the app store, and many report that they collect various bits of data. Are you saying that there's a special content blocker component to all of these that can't collect data because they're isolated by iOS? I'm not sure how anyone who isn't a iOS developer is supposed to navigate this. To uBlock's credit, their App Store page reports that they collect no data, but is this enforced by iOS? Or just a checkbox that the developer clicked?