Let's stop spreading this corporate propaganda. Microsoft's goal is to kill software freedom, and the goal of these Github articles is to give the company a facelift. If open source is democratizing gamedev so much, howcome Microsoft's DirectX is still proprietary? Get the hell out of Github and stop spreading this naivete on HN.
DirectX is (and as far as I can tell, always has been) free to use by anyone.
Which part of DirectX would you like them to open-source that would improve accessibility?