If Google "breaks" AOSP, I am pretty sure that the next big thing will be a fork of AOSP. But that would probably be bad for Google (they probably wouldn't want Samsung + Huawei + others to start maintaining a fork of AOSP, I think).

As far as I understand the distributor licensing for Googles apps and services outright prohibits manufacturers from selling any unapproved or Google free Android devices in countries where that isn't considered anti competitive.

It's a pretty weird subject: the document that has been mentioned in the press about that requirement doesn't exactly say that Google app are required, it says that when you do an "Android" it must always comply to Android APIs. Which can be done without Google apps. BTW that agreement still exists even where it was deemed anti-competitive, but in domains where Google isn't a monopoly (like cars).

That being said, it's Google. Even you didn't sign anything that says you're not allowed to do Google-less Android, when you launch a non-Google device, Googly devices may just "mysteriously" fall into "oops sorry we are understaffed, we don't have time to handle your requests".

I don't know where you can find that "only a few thousand" people or the funding. I don't know if one can even count the number of failed attempts at a mobile operating system.

Do you not participate in any open source communities? Many have thousands of participants, even obscure Linux window managers.