I wonder if someone will eventually make a desktop OS that is entirely web-based. No GTK or WinUI - everything is a web app. Except that the DE would also be, technically speaking, a web app itself that shows other web apps. Kind of like this, except imagine if the example apps ("File Explorer") were real web apps loading into the web app desktop environment.

I think Firefox OS was the farthest that this got, but I think it has potential. Such an OS would basically just be Linux + Headless Chromium + web browser API abstractions for things like USB (WebUSB), etc.