> "It is a big enough OEM that there is good chance you may have owned a device from them in the past."
I think this takes Nothing out of contention.
I'd love for it to be Framework.
As OnePlus is kinda dead and taken over by oppo, I'm guessing Sony. They have some similar collaboration in the past like with Jolla. My Sony XA2 was one of the few models that could run sailfish.
I don't think that there is any need to restart a new category. Just make your new phones good enough for GrapheneOS.
GrapheneOS has close to half a million users, I think it's worth doing some adjustments.