RobotChickens The school can't control authentication for the app like that. It's up to the developers because eacounts is used by a lot of campuses nation wide. It wouldn't be a decision for my school, it would be a decision for all of them.
Almost certainly using eAccounts was a decision within the school's control. Any given school may have limited leverage in terms of asking eAccounts to support more payment methods, but if enough schools ask for it (or threaten to switch) then the company might make changes, since that is technically possible.
RobotChickens Also, adding a toggle in developer options doesn't mean that every single person with graphiene would enable it? Absolutely not 300k devices. The only people actually enabling it and "spoofing" their phones would be the ones who don't yet use graphiene for this very reason. (Or people like me who are using it but with compromise)
My understanding is that the GrapheneOS project has decided, using their best judgment, not to pursue spoofing old device models (other8026). Because the GrapheneOS project is open-source, people who do wish to pursue spoofing old device models could build their own forks. That might go well, or it might go poorly, but all indications are that the GrapheneOS project does not intend to run the experiment. I suspect it would be more productive to pursue a private GrapheneOS fork with device-model spoofing than it would be to try to convince the team that they have misunderstood the technical issues, costs, and benefits. Please note that I do not speak for the GrapheneOS project.