> and they are legally allowed to fingerprint grapheneos and block Play functionality.

No, and you also don't understand how the Play Integrity API is implemented.

Google has a bunch of monopolies tied to Android. Antitrust laws put limits on what they're allowed to do which Google has been egregiously violating for many years.

Google isn't legally allowed to pull a bait and switch with Android by changing it away from an open platform and open source project. They used Android being both of those things to build and expand monopolies in a bunch of areas. The way Google exerts control over OEM partners with Google Mobile Services licensing has already been found to be illegal in multiple countries and they're in the process of losing more court cases over it. South Korea found their terms to be highly illegal and Samsung is already largely free from their restrictions.

Play Integrity API enforces the Google Mobile Services licensing model. The licensing model and terms are highly illegal in countries with decent antitrust law. It has already been found to be illegal by the courts in multiple countries. EU and US have particularly strong laws where they're egregiously violating and that's going to have consequences.

Play Integrity API is primarily based on hardware attestation, which is not fingerprinting. The strong integrity level fully requires hardware attestation and services using it are migrating to enforcing that. Device integrity level requires hardware attestation for devices known to have a working implementation which is a major loophole but it's gradually being closed. Play Integrity API also has many software checks.

Play Integrity API software checks require having an immense amount of privileged access which means it's not very compatible with sandboxed Google Play without an immense amount of work which would achieve nothing. Tricking all the software checks won't make it start permitting GrapheneOS. It's not feasible to pretend the device is one without hardware attestation while avoiding it being detected that it's being faked. None of this can be feasibly bypassed in the long term without it repeatedly breaking and becoming increasingly impractical to bypass. Many apps already require hardware attestation via the strong integrity level and eventually Google will close the loopholes for the device integrity level.

> maybe once that happens grapheneos will finally take anti-fingerprinting seriously

It isn't fingerprinting and no amount of anti-fingerprinting will bypass it. Hardware attestation exists and it provides the device model and OS. It's also easy for apps to detect those in many ways. Apps can just look at their own memory and see the OS libraries loaded into them. The only way to pretend to be the stock OS even without hardware attestation would be making essentially no changes to anything since apps can look at a lot of OS libraries, etc.

Running apps in VM wouldn't solve anything either and will only work for apps which don't try to detect being in a VM and don't use hardware attestation or the Play Integrity API. We'll still need to support running apps on bare metal once we have VM isolation features since one of the main things apps doing these anti-tampering and attestation checks is trying to block is being run in a virtual environment.