Don't modern versions of Windows do the same? For example, I clearly remember that the Windows 10 installer first launches a Windows 7-like environment.
It continued as 6.1, 6.2 and 6.3 for Windows 7, 8, and 8.1. But the NT kernel revamped for Windows 10. And they aligned the version numbers at that point. Windows 10 and 11 are both NT 10. The kernel has many differences within 6.x let alone the big leap to 10.