[IgorPartola]

The thing is that Android is open source (at least nominally). So having Google refuse carries the ability to customize it would be like having the Linux project say that companies can’t ship their own distros.

Google could have applied pressure on carries via some sort of “Certified Android” label but realistically this is very different from iOS/Apple where the hardware and software are closed and made by the same company.

[NewJazz]

Google Play Services, which is damn near essential these days, is not open source by any means.

They might have had a harder time applying pressure on carriers early in Android's lifetime, but there is so much momentum in the ecosystem now that they can do it easily IMO.