to be fair, there's a large graveyard of OSs which failed to gain traction, especially on mobile.
I'd be surprised if any vendor adopts Fuchsia thinking it has anything better than a 10-20% chance of being mainstream.
Today we have Android and iOS as the dominant Mobile phone OSs. Don't forget about all the attempts to dethrone those two by: Symbian, WebOS, Windows phone, Blackberry, Tizen, Ubuntu Touch, kaios, firefox os, PureOS, LiteOS,...etc.
