They can impose whatever they want to OEMs who want to ship the Play Services and Google apps. That's pretty much all of them.
If they say "install it this way or no Play Store for you", every manufacturer will follow.
That is what I have been wishing for years, and yet they still choose not to do it.
They almost certainly cannot do that in Europe at the moment given the regulatory situation. Indeed, I expect to see far fewer restrictions going forward, not more.
Why would they do that? Isn't Play Store the way Google monetizes android?
Actually, this is not an allowed customization.
Then spend one hour of your life listening to ADB Podcast, where Android team explicitly states that, saying that they don't want to encumber the work of them creating unique experiences.