This makes a lie of the whole notion that Android is open source. Yes, the skeleton is open, but the guts are proprietary. And the skeleton on its own is useless.
Android (AOSP) forks are numerous, yet competing with Play Store/Play Services seems expensive and onerous. Nontechnical consumers don't see Amazon's Fire as Android, just an Android-like system that runs many Android apps. Nontechnical consumers thought the same about CyanogenMod (the Company)'s efforts. Samsung's Cold War seems so desperate, from the outside, because they are trying to walk that fine line between remaining a consumer Android and yet still distance themselves from Google's control.
But yes, in rest of the world non-Google Android is struggling.
Without any first hand knowledge, I'd assume that the balance of things towards WeChat and away from Play Store/Play Services in China might mean that "Android" really does mean something different in Chinese markets? It's easier to sell an "Android" device if the benchmark is "runs WeChat" rather than "runs the apps I see advertised everywhere" (given the near ubiquity of Play Store emblems on American ads) and "runs the collection of apps I've bought over the last few years from the Play Store".
I don't know where you learned about the misinformation that is "the balance of things towards WeChat and away from Play Store/Play Services in China", which is frankly quite ridiculous because WeChat is just a messenger app with a few added functionalities (social timeline, payment, etc.) — it's not comparable to an app store or a service SDK at all.
Back to my original curiosity, outside of my supposition you think is clearly wrong, do you have an impression that Chinese phones that have forked AOSP and don't have access to the Play Store/Play Services still count as "Android" in China? If so, can you give an indication why that might be different than in America where Play Store/Play Services are nearly synonymous with Android?
Nothing about open source requires that they in any way stabilize their web-side APIs, the process they would follow could be the same as their binary releases, just with open source code released at the same time.
This is assuming that Google wants people to see and be able to use these APIs in the first place.
I understand the concern, but I'm not sure I believe it's really that significant.
1. They could release source and provide no guarantee of supporting API backwards-compatibility, exactly as they do today, only with the source available publicly.
2. They already deal with API deprecation. Owning the client doesn't get it to every device instantly. Even logic pushed into Google Play Services requires a (sometimes lengthy) rollout and relies on customers to approve the install.
To be clear, the discussion isn't about whether Google should pull things out of AOSP and put them into Play Services. The discussion is about whether Google can open the source for those components. So long as Google owns the copyright, the answer is a clear yes.
"Led to believe"? Is there any dispute about the fact that most Android manufacturers deliver major updates very slowly and often not at all?