I want a Linux phone because Android even when fully degoogled and secured like in GrapheneOS is still beholdened to Google's grip on their proprietary Play Ser

I want a Linux phone because Android even when fully degoogled and secured like in GrapheneOS is still beholdened to Google's grip on their proprietary Play Services framework and 'SafetyNet'. Basically tons of apps are crippled and non-functional unless you let Google's code run as a system app. Sure it can be tricked, spoofed, and mocked for the time being but doing so basically destroys the security model of Android in the process. There's also a lot of badwill between the 'secure' Android ROM groups which isn't great when the selling point is security and reliability. A proper Linux phone with a Secure Boot/Verified Boot implementation would be great. Linux phone's ATM seem to be more concerned with userland stuff like camera apps. In a way, a Linux computer in the form factor of a phone with a modem is probably best but it's the complicated nature of the ARM ecosystem getting in the way. e.g how many forms of a secure boot system for ARM exist between Android, Apple M1, Samsung Knox, et al. Regarding the camera... I don't quite see why a camera system using MPV + standard webcam capture tool can't be used... I guess it's not user friendly but it would be simple. It's not like Linux+Camera is anything new.