I hope GrapheneOS isn't completely banking on their partnership succeeding. If Motorola devices ever became the only devices that GrapheneOS works on, and it's being done with Motorola's blessing, then it could be more easily legislated out of existence.
Having said that, the hardware being restricted to Pixel devices was always a tenuous proposition based on Google's design choices. If Pixels remain supported whilst adding Motorola, that's only a good thing.
Google's Pixels have been one of the most open Smartphone hardware lines though. Only a small handful of vendors support Android Verified Boot with custom keys.
GrapheneOS did not wall off itself or anyone else. The lobbyists who wrote those laws walled themselves off. I think they need to pay for the damage they caused with those laws privately. That way they will stop acting as lobbyists for private entities such as Meta.
https://grapheneos.org/install/web#hardware-based-attestatio...