Source is this video:
Windows Was The Problem All Along - Dave2D
We could obviously compare performance between windows and steamOS before on the steam deck, or between windows and Bazzite on other handhelds. But this is the first time we have had official windows and SteamOS builds for the same hardware.
Because they aren’t just optimizing for gaming.
Any change they make would influence their other markets as well, like general and office use.
They made an attempt. It’s called Windows RT. It’s a sandbox more locked down than iOS.
The Win32 desktop environment isn’t built to support stuff like “timer coalescing” for all the API calls which all the software is designed to run continously in the background. Changing how it idles would change so many things which all kinds of software depends on that it would barely be the same OS anymore.
Realistically the design goals of a gaming OS vs a general desktop OS aren’t that different. You want to balance performance, batterlife/power consumption, and making sure it withstands insane abuse by users and software doing anything you could never imagine that nobody should have ever tried to do. About the only design goal that separates SteamOS from Windows is fleet manageability features
You are forgetting backwards compatibility with ancient software that Windows still supports after 30+ years.
A lot of businesses need that in order to function.