> Android users need to switch to Graphene.

Which supports only Pixel devices.

The resason is that only Google bothers to put enough hardware security features to build software on top that allows to make a really secure device that blocks tampering.

That's not a reason. When the hardware doesn't have those "security features", then don't "really secure", just run without being "really secure".

I never treat my (Android) phone as secure anyway.

Security is GrapheneOS's raison d'être. If you don't want security, you can run another Android build that does run on the hardware you have.

Well, they're not improving people's security overall by limiting themselves to Google's hardware.