You're right—GrapheneOS is AOSP-based and often runs on Google hardware. Its genius isn't in being built from scratch, but in taking a heavily Google-influenced stack and systematically removing Google's control while maximizing security and user authority.

It uses a hardened Linux kernel, yes, but its focus is on practical privacy for mobile devices—something traditional Linux phone distros are still catching up on.

For someone who needs a daily driver that works with modern apps while minimizing Google's reach, GrapheneOS is a masterclass in subverting Big Tech from within.

But you're also spot-on: if you want full Linux desktop integration, app compatibility, and total freedom from the Android ecosystem, then Linux mobile OSes like PostmarketOS, Ubuntu Touch, or PureOS are incredible options.

It's not either/or—it's about choosing the right tool for your threat model and needs.

GrapheneOS for a secure, Android-compatible, Google-minimized phone.

Linux phones for full desktop convergence and total software freedom.

Both are valid. Both are vital. The goal is the same: take back control.