I agree with that but i also believe that MS is doing this for money.
Since there is no free upgrade now many will have tp buy W10 and especially enterprises
It is another measure to force OEMs to install only Windows 10. It is to prevent users from installing anything other than Windows 10 on custom-built systems.
It just means that on newly minted Ryzen systems, the system owner cannot "downgrade" to Windows 8\8.1, 7, Vista, and XP.
No one will be forced to upgrade to Windows 10 because Ryzen systems are very new - but they will have only a single option for Windows on Ryzen systems - including custom built systems - and that's Windows 10.
I haven't seen pre-Windows 10 installed on any Kaby Lake systems. As far as I recall, Microsoft banned OEMs from installing pre-Windows 10 on Kaby Lake systems. But, of course, if there are any, then they will either have to use the Assistive Technology free upgrade for Windows 10 or buy a Windows 10 license.
Of course... this entire Windows 10 rigmarole is all about money... just about everything Microsoft does is all about money.