Porting code for something like Windows isn't trivial. Considering the reception that Windows 8.x got, doing this kind of work for an OS that never gained traction that's less than a year away from the end of mainstream support, probably not worth it.
I've said from the beginning blocking Windows Update was a bad PR move. But backporting kernel code to support the latest and greatest hardware for an 8 year old OS and one that was never popular? No one would even be talking about that if not for a stupid PR move here by Microsoft.
Again don't defend this on technical grounds... it doesn't hold water.
This is a marketing decision intended to force sell copies of Windows 10. Nothing more.
The technical arguments all fall apart and you know it. Supporting a few minor code changes for a CPU are not hard things to do... if MS honestly can't do that they need to hire some actual engineers. The code that needs to be added or changed for the Linux kernel is less then the number of changes to support a new Wireless controller. Not to mention that ALL of that code was supplied by AMD. The major commercial Linux vendors that run older hardened kernels have had no issues back porting that code.
Supporting newer CPUS for MS is no different. Its 200-1000 lines to support a handful of new features... and another few hundred lines of code changes to existing modules. Again code that is supplied by the hardware manufacturer, MS doesn't have to code for Intel or AMD hardware... I doubt highly either would give MS the information to do so.
So by all means argue if you wish that MS should push everyone to 10 cause its best for them, and damn what a small handful of their customers want. If you believe that, cool by all means argue that. Don't however don't insult the average [H] readers intelligence by suggesting its not trivial to add support for a new CPU. It is trivial for MS... it would cost them exactly as much as it costs them when Nvidia releases a new GPU driver. AMD and Intel code drivers and supply any needed kernel changes for their hardware.