If Windows marched their software updates on the same schedule Apple does 50% of Windows software simply wouldn't keep up. Lots of Enterprise apps only have one version that's even compatible with Windows 10 since 2015. 2015 was iOS 9 era. Many manufacturing systems still run Windows 7 or XP even because the new software doesn't support existing machines worth millions.
Microsoft has to keep all that baggage available with some form of compatibility even in Windows 11. Or they would leave tens of thousands of businesses behind. And businesses and business software (Servers, SQL, Visusl Studio, etc) is what pays Microsoft's bills, they make little money off PCs.