I agree with you to a certain extent, fade2grey. I believe that you are absolutely right that if CPG supports Windows, it should also be supportive of it. But (there's always a but) as far as I've reckoned, the people who most often run Windows boxes are also the ones who most of the time have the least clue about what they're actually doing. And no, I'm absolutely not "ranting down" on anyone, I just say what I believe (I run a Win box on my test site btw, though I'd never run it on a live box).
I believe that's why people here on the forums maybe are a little less prone to supporting Windows than other operating systems (Linux, BSD etc). In 98% of the cases, if someone actually knows what they're doing on a Windows box, they won't ask for support here (regarding OS related questions). And even if they do, chances are that they are asking questions that have already been answered before. Most of the time you can actually tell from the post (or a couple of posts) if whom you're talking to knows what they're doing or not. Not that it should matter in that sense, as every Coppermine user should have good support anyways. And they do get it - afaik there's not many support boards around that are as helpful as this one is. But many times it's pretty clear that some people really shouldn't run their own boxes, and when that's shining through, it sometimes may sound a bit harsh what supporters here are saying when all we really want is the best for all users.
The more users who run their Coppermine installs on solid, secure *nix systems and the less who run their live installs on half-patched, insecure Windows boxes, the safer the web will be for all of us - I believe that's why many here are rooting for users not to run their own Win systems.