The only trouble is, it's locked-down Google/Linux that they're using, not GNU/Linux. All the freedom and user empowerment has been neatly excised from it such that it only facilitates consumption, not creativity.

And within that frame, I'd be very surprised if it ever breaks out into the mainstream. Google brought android to the world as a vessel to make money. You very rarely hear about GNU in the wider world, outside of tech circles, being promoted to the masses as a viable alternative specifically because no one stands to profit from it, and they can't have that.