There is no question about it, Windows is in the 'mature' state of its lifecycle and while it's not going anywhere for a very long time, it's also not as critical to society and the corporate world as it once was back in the late 90s and early 2000s. That being said, Microsoft is transforming how and where Windows runs to extend its life which has been the basis of the 'new' Windows narrative.
Starting with Windows 10, Microsoft scrapped the old convention of slow update periods and is incrementally modernizing the aging OS; some parts are 30 years old. With new features like S-Mode and the ability to once-again run Windows on Arm, Microsoft is creating a new narrative for Windows.