I would be curious about the feasibility of a “performance mode” that was basically “reboot you into a “single program” mode”. I assume it would be unreasonable given so much software relies on the tools modern OSes provide, unless the software itself was made with this in mind.

You’d imagine some giant like Adobe would figure out a way to run dedicated machines, given they have so much software that uses lots of resources. But then, as best as I would find it for games, I imagine most people don’t want to give up alt-tabbing to their web browsers.

I think I heard the idea related to ChromeOS. Most people use their computer solely for starting a web browser. Sooo ... why not make the computer boot into a browser then?

I often use nothing but a browser. When I'm doing productive / creative work, even often with games, I still want to have a browser.