Android is very opaque about what is actually running. I was walking by a shopping area with a new phone recently and Google Maps popped up with some irrelevant notification. But upon viewing running apps, Maps was not in that list, so there's basically an unknown number of useless background tasks running that the user cannot view or control.
As a whole, Android is pretty terrible. You can't run the things you want and you can't stop the things you don't.
Google's best interest is to vendor lock users on it's plstform and retain the maximum amount of control over Android. They won't give it up voluntarily, that's why I used the word 'forced' in my first post in this thread: now it can happen only after a binding legislation, and, possibly, breaking up Alphabet.
As a whole, Android is pretty terrible. You can't run the things you want and you can't stop the things you don't.