and how long before a PC dev has to pay MS for each sold copy (just like console games)
That's an impossibility.
Not only is it an open platform (for developing on,) but the lawsuits over what defines a game and what defines an application would be insanely costly. You'd have devs start bundling basic word processors with their games to get around it.
Furthermore, why would MS be so stupid? They know damn well that every other platform on the market is open to any development. They know the reason why theirs triumphs is the amount of applications available for it. If they start charging people to develop for it they give incentive for people to develop elsewhere, which gives consumers incentive to investigate other markets.
I think you're missing a couple of important details. What I was saying was, if DX and GFW become so big/important, that in order to create a
competetive game you need to use those, then you have to pay MS what they want. Right now DX is free so no problem, GFW is not. Since MS owns both, they have every legal right to introduce fees and royalties to any of those components. Which in the long run can mean the scenario I was describing.
Yes, the windows/pc platform is open, so you can still make apps and games without paying MS royalties, but I was talking about doing comptetitive games (meaning once it's at a point where a consumer wouldn't look on any game not having GFW and DX12 stamped on it).
The DX dependcy is especially critical when it comes to 3D HW, we're already witnessing the trend that the new HW generation will have functionality, only accessible through DX10. If that trend continues, at what point is OpenGL no longer feasible, leaving the developer no choices of API/OS/platform, again if they want to stay
competetive. (also even when doing GL games today it's pretty usual to use some of the non-3D parts of DX.)
I'm not saying this necessary
will happen, and it's not some anti-MS rant. I'm just being cautious about the whole thing, I don't like the fact that one and the same company (not that it's MS in particular) would be in control of all the crucial components.