Android TV is not AOSP, it is an Android variant actively developed by Google and requires Google Play Services.
Kindle Fire is based on AOSP, that was my mistake. I will say Amazon is a rare OEM in this regard; they're tablet-only, and happy with AOSP because they have their own app store that don't need Play Services integration.
In the tablet / phone world where end users expect to install applications from the playstore yes but there are many other device types that do use AOSP.
For instance some parking meters / train ticketing machines / payment terminals run Android. source: I work for company that makes some of them though we are moving away from Android to more classical embedded Linux.
Google play services doesn't matter in these contexts.
Your point is actually a good one because Amazon has abandoned its app store infrastructure. And it likely will just integrate Play Services in future.
