I'm not seeing this as much of a problem. Windows is a dying platform because of a multitude of bad decisions like these. If they choose not to implement it, less software will be made for Windows, accelerating its demise.
People will continue writing software for windows for as long as it remains the dominant platform. What happens is that they'll use other languages such as C# (which is perfectly fine for them)
Of course people will continue to write software for the platform. I never said otherwise.
But there is a ton of software being written right now that doesn't target Windows, with no plans to target Windows. The only way Windows users will ever be able to use that software is if Microsoft makes it easy enough to port.
The nail in the coffin will be when most of the games on Steam do not work in Windows. With most business software becoming web-based, the only holdouts left will be old businesses locked into their enterprise crapware.
