Is it really Google's Android? I have the feeling it's mostly Chinese manufacturers with their own Android versions sans the Google services.
When they sell them in China, yes.
But the same manufacturers sell Android phones with Play services in Europe, Japan, India, Indonesia, etc.
Android is still developed by google, yes.
The chinese are mostly adding skins on top, not developing the core of the operating system.
There is however a chinese fork of android (state sponsored), but it has not gotten wide market adoption in china either to my knowledge, but i dont live in china so i'm open to be corrected.
Finally, even if that OS has gotten widely adopted in china - it IS a fork. the changes are not being upstreamed to android, hence irrelevant to the discussion on this forum.