I would be really happy if you’re right, but I sadly think Google’s fine here. As far as I understand it, this particular regulation is to prevent a powerful actor (Google, Apple) to use their monopolistic powers to shut alternative stores down. It’s not about allowing customers to install whatever and however. Google doesn’t shut anyone down with this, so they should be fine. They give the option for app developers to choose if they want to run only on an attested platform - which they sell as a completely optional security feature that nobody has to use.
My guess is if the EU is going to take this further it would have to be regarding a potential monopoly on the attested platforms on the device. Google only offering their own platform as trusted could potentially be seen as another monopolistic behavior. If we’re lucky.