I think a lot of the appeal of TempleOS is a certain nostalgia for a world where single coders would do something amazing on their own, and nobody knew what "UI

I think a lot of the appeal of TempleOS is a certain nostalgia for a world where single coders would do something amazing on their own, and nobody knew what "UI/UX" even meant. A more naive time, with less specialization, where people just wanted to create something cool. You can prove me wrong, of course, but why not just create a completely new UI on top of the Linux kernel? The Linux kernel is completely agnostic in regard to user interfaces.