If you're playing games only in desktop mode then you're throwing away most of the benefits of SteamOS. You could install Steam on any Linux distro and have the same experience.
Gaming mode skips running the entire desktop environment and runs games in a minimal environment. KDE is fairly lightweight already but come on, how can it compete with something that just displays one window filling the whole screen?
Some mods are way easier to run in desktop mode, plus I can’t open a browser window or discord or anything when in gaming mode. Gaming mode is great and gets you more power but it also removes the ability to easily access things (or removes access entirely) some of us like to use while playing.
It’s fair to assess the full desktop experience, especially when it’s a core part of the device.
Easier to run or set up? I don't see how it'd be easier for anything other than setting up.
> I can’t open a browser window or discord or anything when in gaming mode
You can, actually! Just add them as non-Steam games. You can have multiple games/programs open in gaming mode and the Steam menu lets you switch between them. Or, if you want it a bit more streamlined, there are Decky Loader plugins that help with these.
But anyway, they’re talking about resource usage in desktop mode and saying it doesn’t matter. I think it matters.