I don't get the first-party library cargo cult that has developed on Android. What's wrong having the community develop libraries like on any other platform? There's a huge set of very good quality 3rd party Android libraries and even a great new language (Kotlin).
As a dev I'd be rather that Google focuses on developing quality core blocks which cannot be fixed by community. Sadly it seems that Google developers simply do not know how to build good APIs, even new ones like MediaCodec, BLE APIs, updated storage APIs and permissions are an utter hard to use mess.