How is that relevant? One of the nice features of a language like Python is that it's very easy to write cross-platform code with it. You really have to do effort to code a python web app on Windows that breaks on Linux. The same holds for e.g. Ruby, Node.js and Java.

I prefer Windows for a dev platform (really, I do), but I've only once written a webapp that was hosted on Windows. I'd much rather prefer unixy servers.