Basic statistics: ~10% of the desktop audience is on a Mac, well under 5% on Linux. So *by definition*, people coming to KDE as their first Linux desktop are coming there from Windows.
Yes, yes, he doesn't actually say that in the quote, per se, but he implies it, and you accept it in your reply.
So the *real* question is: who set those machines up, and what did *they* prefer.
And yes, KDE (3, and now 4) was the preferred desktop on SuSE, all the way back to, I think, 9.0, which was my first version of that work.
Note that what you're *really* replying to is an assertion he did not *make* in the section you quote: that people coming from windows are *going to* KDE. He's talking about the people *already on KDE*, a different proposition entirely.