Which presents itself as a much higher barrier. Only the smallest fraction of Windows PCs have these layers enabled/correctly configured, for it to run.

Virtually all Windows PCs have a Browser installed and running. Most users know how to open and operate a Browser.

Of course it's kind of redundant for everything to be reimplemented into the browser, things that should be implemented and used on a OS level, but I think it's a testament of the shortcomings of the UX design or even more fundamental paradigms of personal computing.