> I wish I had something like GrapheneOS on desktops

Secureblue is essentially as close to GrapheneOS as Desktop Linux can get. Neither my response nor the original question required qubes comparisons. It was merely mentioned.

> grsecurity® is the only drop-in Linux kernel replacement offering high-performance, state-of-the-art exploit prevention against both known and unknown threats.

While secureblue is a full desktop distro (not just a kernel) that integrates key grapheneos hardening tools like their hardened malloc and forks of their hardened chromium and works with flatpak as a base for hardened application deployment.

grsecurity does literally none of that.