I do game, but I do not always game on all the screen. It depends on the game and the focus I want.
For example, e-sport, I use 2/3 of screen to game, 1/3 of screen for browsing and discord.
For solo gaming or a game needing focus, I play fullscreen.
league of legends works really well in 32:9 ! But I use it in 21:9 (2/3 of my screen), which already is an ultrawide ratio.
Civ 6, Baldur's gate 3, witcher 3, work well in 32:9 (using the full screen). No worries here. Humankind too.
For some, there are adaptations but it works too. Skyrim or fallout for example. There is a software named "flawless widescreen" ; it improves the experience for initially poorly compatible games.
I do use a software for windows layouts with macros. Meaning I can switch the disposition of my browser, explorer, discord, signal, pdf or anything and my games depending on what I want to do. And that, is really enjoyable.
Well it doesn't support browsing its library by folder, which is a no-go for me. I use gonic.