Stock Android is just as bad yes. But Graphene isnt perfect. Degoogle term is a lie. You cant degoogle literal google hardware lol. Pixel phones are made from a company that goes against freedom, privacy and ethics too.
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Yup, GrapheneOS on Google Pixel phones has seemed like a temporary strategy that has turned into a permanant one, but ultimately the hardware _also_ needs to be degoogled.
Pine64 and Librem and the two hardware options that seem to be on the right path there, however there is quite a bit of work yet in getting mobile GNU/Linux mobile ready, it's much closer though.