Everybody is so quick to forget about "Android fragmentation," but fragmentation is a clear indicator of Google's lack of control over Android.
In reality almost everyone nicely complies with google's compatibility definition, constraining how far they can fork android, just in order to get access to google's closed source apps: https://play.google.com/store/apps/developer?id=Google%20Inc...
Only amazon has managed to make a viable usable fork of android that complies with legal requirements, and the amount of work it took them was prohibitive for anyone not on amazon's scale.
Android as OS is open source, but android as experience is very much under google's control. Like i said though, they have been quite benevolent, because they view android as a vehicle to get you to use the google services.
Not to hundreds of millions of Chinese Android users.
The point of the CCD [1] is to ensure that new devices can run a test suite that ensures they work correctly with Android as it currently exists. CCD isn't just about Google Play and Google Play Services, its about the fundamental functioning of the OS.
[1]: http://static.googleusercontent.com/external_content/untrust...
I don't think they are more responsible, they have to be this way. When given dominance, they also use it to get you signed up for other products. See Google+, it is not is search, you need it on Youtube and what not!
Samsung is a hardware giant. They suck at software and can barely handle a thin customization layer on top of Android and anyway they seem more interested in flooding the market with hardware rather than consolidating.
The other Android players are not making any money, building the backend infrastructure to compete with Google is a billion dollar type project.
It also takes time to determine what is abuse and what is not. Especially in behind doors deals. The case of Google threatening licensee to lose their license if they ship unrelated product Google does not like would definitively be abuse plain and simple. But as most things people discuss on the net, that's just based on rumors, who knows the real dynamic at play.