If you're asking what platform they like to use, when developing, it seems macOS is the preferred platform. If you're asking which platform has more programmers writing code, i.e., windows programs vs. Mac. I'd say windows, just because of the percentage of the market windows holds over macOS.
For instance, we have many mac users at my site, you can request a mac if you want, but there are zero, absolutely no mac specific programs that used, all business applications are windows based (or cloud). I know one employer does not make a trend, but I think overall, the enterprise sector is more likely to have windows based applications then mac based by a high margin.
Then there's the linux platform, while desktop Linux has not taken off, Linux holds a commanding lead on the servers, so they may very well a high volume of developers as well