What would get me to stay with Linux (I've been going back and forth for the last few years) would be a fully-featured File Explorer work-alike complete with previews of every file type and a full-on context menu copy. One other thing... the ability to right-click any program icon and pin it to the taskbar. They're little things, but whenever I find myself on Windows 11, those are the things I find I missed most... well, other than being able to run File Locator Pro, NotePad++, and Bulk Rename natively.
Oh, and getting some part of the OS/window manager to remember window placement/size. Wayland/GTK don't and this is NOT an innovation, it's trying to turn the desktop into a phone.