Re: It's bold, it's innovative, and ...
"KDE has nothing to lose. There are no allies or affiliates to annoy or estrange.
More of this sort of thing, please."
I agree it's a good thing to do. But it seems they're trying to do two things at once. One is produce a KDE showcase, the other is to try out all sorts of more or less experimental system architecture stuff. Both are laudable things but the latter isn't yet mainstream. As a regular KDE user I'd be very reluctant to switch to this as a daily driver; if the underpinnings were more mainstream I might. In that respect I find it difficult to see it as something to offer as a Windows replacement.
OTOH I can see how it would be a Windows replacement for all the wrong reasons. If its far enough off the beaten track it could be set up as a vendor's OEM installation maintained by the vendor's OEM systems and if the vendor then declares EOL there's then no chance of doing an apt distupgrade; it's upgrade by land-fill time.