The big thing is that the Deck uses Linux which allows Steam to provide an amazing interface
For most people, i think it’s just that it has a good UI. They don’t bother whether it’s linux-powered. Maybe it’s possible to create a good UI in windows as well, but it will be bogged down by 100s of unwanted processes.
No, Microsoft don’t allow it. As part of the distribution licence you are not allowed to customise the OOB interface.
People don’t know it’s Linux, but it’s absolutely because of Linux that it works.
Absolutely. But they want everyone to know they are using Windows, which if there was a custom shell then they wouldn’t.
They have >95% of the market, they don’t care about making a good interface for TVs as they already lost it to Android, and they don’t care about making a good gaming interface as they already have XBox.
Windows users are an inconvenience, that they want to milk.