[sinh]

Well, if Linux developers are better paid this will naturally increase supply. And this happens, of course.

But why should pay companies more for Linux when they can develop stuff on Windows, and pay less? Wouldn't it be dumb to use the more expensive resource, and have less gain? The reason is that Linux developers are more productive - they create more value, and the decision of companies to pay them more is all rational. Of course the detail picture is more nuanced - it makes a difference if one develops a boring PHP app, or makes complex embedded systems for sectors like HFT, defense, embedded medical devices, or similar. But chances are that a lot of the latter use Linux, too. They just don't advertise jobs on HN.