Operating systems are the systemic risk to crypto.

If compelled by the state…Apple, Google, and Microsoft can backdoor billions of devices through software updates to scan for private keys.

The capability exists.
https://www.theverge.com/2022/12/9/23500838/apple-csam-plans-dropped-eff-ncmec-cdt-reactions

Yes, we need something like ethOS, Solana phone, or Qubes. Maybe an Urbit box.

An ultra secure operating system for desktop & mobile dedicated to crypto.

We also need to move enough funds on there in a relatively short time to make seizure unattractive.

This is hard for anything but an Android fork, and even then...

Calyx is a fork of Android that's fully open source and runs any app that you can run on Android. The only drawback is that it only works on selected devices. It isn't crypto-specific, but it pretty much eliminates the possibilty of backdoors.