Any improvements with fractional scaling? Can anyone please link to any material reg the work being done for improving fractional scaling in Linux; it would be great if it could match the rendering quality of macOS.

Fractional scaling is now supported by major toolkits and compositors.

https://wayland.app/protocols/fractional-scale-v1

Also, I wouldn't hold the rendering quality of macOS as a high standard at all, since all it does is render at a multiple and then downsample, wasting energy and introducing blurriness.

What's your setup like? I'm on AMD+Wayland+KDE, no complaints with fractional scaling on my ASUS ProArt PX13 (255 PPI screen).

IME it works fine on Intel iGPUs, too. I even use multiple ratios with no issue (constant 125% on the laptop, 100% on an external screen and 200% on a different screen at work).

Contrary to Windows, this also works well when hotplugging screens. Menus don't end up a blurry mess, and apps seem to work fine. On Windows, even some 1st-party apps are borked (task manager comes to mind).