> an OS developed specifically for playing games This is what consoles try to achieve. And they do one better by not having to deal with countless combinations

> an OS developed specifically for playing games This is what consoles try to achieve. And they do one better by not having to deal with countless combinations of hardware and software. They are optimized (performance, stability, compatibility) to run games on unified setups and with a guarantee they will run for years. They also curb piracy and cheating which is something the videogame industry really wants. The downside is not having the leading edge specs every year. The problem is the market for a very gaming-focused but still general OS that can run on generic hardware is just not that attractive for most users of the videogame industry. And truth be told I doubt it would be any better than any generic OS you already have now. Personally since XP SP3 the biggest problems I've had were almost exclusively with drivers, save for a few Spectre/Meltdown mitigation issues.