For me, it’s Shared GPU memory.
Well, I also tend to consider ultrawide monitors a mistake in their own right. Why would you want a 49" wide literally anything if it’s not some kind of immersive media experience where menus are irrelevant anyway?
Of course, if that is in fact exactly what you bought it for, I have no complaints. Even if I disagree with having one for other purposes, that’s still no reason for the OS to punish you for having one when you try to use it that way when that problem is completely avoidable.
It’s also great when programming. I usually have an IDE/text editor, documentation/browser, email/teams and a couple of terminals open at all times and being able to see all of them at once is really helpful.
Granted, you could get the same with two 27" monitors, but add ultrawide gaming to that and it’s pretty much a no-brainer for me.
I’d rather have multiple monitors so I have the more intuituve window snapping. But to each their own.
I’m firmly in both camps. Window snapping is much more flexible on a single monitor- I can’t really do quarters on a side-by-side setup, but I can on an ultrawide. However, I love having a second monitor in portrait.
Until they make T shaped displays that I can mount sideways, to get the best of both worlds, I guess my best option is a single massive screen, where I only use a thin strip of one half.