Isn't that what GrapheneOS is doing?

Mostly agree. But they're doing this only for Google's Pixel devices. I doubt that Google won't find a way in the future to prohibit or make impractical the use of GrapheneOS on their Pixels. Are you confident that Google won't?

How feasable is it that graphene, lineage and iodé unite forces to fork android and go on in the privacy road?

#asknostr