“Consumers are attached to the Google products and services that sit on top of the operating system,”

I doubt that. Google is pretty bad at keeping users. (Probably GMail is the strongest anchor point, but as we have seen with the G+ real name gotcha, it's better to be prepared to stop using that. Though of course most GMail users are not prepared for that.) Users will use whatever is the default.

Probably the YouTube app is what users would miss the most. And I don't know whether it works without Play Services. But it certainly works on iOS, so if there were a new platform, Google/Alphabet/YT would make apps for that platform too.