Both Ubuntu and GrapheneOS don't allow you to fully control you phone like Linux desktop does. However Librem 5/Pinephone can run PureOS/postmarketOS that do.
It's easy to say, "Just don't use that stuff". But if everyone wants ("needs") it and we don't have it, then we're left with a <1% user base of activists and eccentrics. And at that point we've lost all influence on the ongoing slide towards surveillance dystopia. It's dispiriting. I'm just hoping that somehow I've got something wrong in this pessimistic analysis.