I didn’t read too much into it, but roughly speaking: Because the technology by design aggregates data immediately and drops any personal identifiers/ the unaggregated data in the process. Other companies can build whatever they want on that, but if done properly, it is impossible to reconstruct user-specific data points and profile the users that way.
This type of privacy-preserving aggregation technique is not new, it is fairly common for things like demographic data, where you want to know things like population density and incomes for some area, without just publishing an exact address with corresponding income for every person (as an example).
Edit: I think I missed your point a little bit. I am unsure, but it seemed that Anonymous is responsible for designing the framework, not doing any tracking (i.e. it wouldn’t necessarily be “put all trust into them collecting it”). Maybe rolling out that technology could be done in a way of blocking other tracking, or maybe it is intended as a basis for regulations to take up. Maybe someone else can give more informed input on that.
That sounds like some bug that should not occur and would of course be painfully annoying. The main advantage of it are the apps it provides, though. Some of them are not available in the play store (like NewPipe, a very good YouTube app without adverts, if that is still around). It is also a good place to start if you are looking for some new app for a specific feature, mainly because it consists of free, open source apps and you don’t have to sift through loads of low quality software that is riddled with ads, collects as much data as possible, or requires some obscene subscription fee, if all you wanted was a flashlight or whatever.