You don't have to buy a new pc just to continue using the internet. (Windows 11 forces a PC to have a modern motherboard with TPM, Windows 10 will reach End of Life and the person is fucked when certificates expire) You are not forced to have candy crush automatically installed on your machine. Your search actually can show your files and programs instead of redirecting to bing. Greatly reduced attack surface, since malware can't go living off the land. Actually faster file transfer over the network. Full telemetry with no possibility to turn it off

The list is a bit random and examples are not that hard to find. Although, almost everything is tuneable and switchable on Windows, which helps it a lot to adapt and reduce pain points mentioned above.

The main actual problem is that it's a corporation controlled, and they don't have your interests prioritized.