It’s important to phrase that the other way around. Windows 10 will be the only MS OS to support new Intel CPUs. Intel CPUs are going to work on anything that bothers to implement the new interfaces. So they will run OSX, Linux, BSD, Android, whatever homebrew OS you feel like building yourself.
This is entirely MS deciding to not bother implementing the xHCI USB controller drivers for their old versions. Which is unusual but not unheard of. It’s more that it’s unusual this short into the lifespan of Windows 10.
Hardware incompatibility like this isn’t too rare. Just OS vendors tend to put a lot more work into doing something about it. The most common one is SSE, or I guess FMA or whatever nowadays, if you get some binary with it compiled in and you don’t have the extension on your CPU that software isn’t running. People have mostly masked this by using DLLs to dynamically switch versions of compiled code depending on the CPU. Or by just incredibly slow uptake of x86 extensions. Back in the 90s it was MMX that did this, or early 90s having some program with floating point instructions compiled in, oh you’ve still got a 386? This needs a 486 minimum. Huh I’ve not hacked any PC, C code in fuck ages.
Anyway article: https://www.theregister.co.uk/2016/09/02/windows_intel_kaby_lake_amd_zen/