Comment by btown

https://en.wikipedia.org/wiki/Usage_share_of_operating_syste... says otherwise; while Android variants have allowed other manufacturers to gain footholds, and some even are "de-Google-fied" in terms of services... all of them stem from a codebase that has been designed to be compatible with, if not explicitly promote, Google's revenue streams.

Imagine, if you will, an adblocker that could run across not just web pages but all apps, in a privacy-protecting and declarative way. Google has every incentive to simply slow-walk the OS-level support necessary for this kind of system, perhaps citing legitimate security concerns, but certainly not allocating resources towards solving the problem in earnest. And if you hard-fork Android to do this kind of deep work, rather than just maintaining packages or patchsets, you'll be forced to dedicate tremendous resources towards maintaining that fork to keep up with mainline fixes/APIs. (And that's just the tip of the iceberg.)

So it's an incredibly effective chilling effect in practice, quite intentionally so.