Not the person you asked, but I use a lightweight window manager and set the screen DPI correctly using xrandr, and/or set the font in each app I care about.

I’ve found this works well across high and low DPI machines.

If you're not doing fractional scaling it works well. But fractional scaling is still rough - in particular all electron apps are blurry

Currently on Gnome+Wayland in a multi display setup that have different fractional scaling factors for each monitor. Usually 1:1:1.5 but I also tried 1:1.25:1.75 for the 1080p,1440p and 4K.

Gnome programs work perfectly. Qt looks good when wayland backend is force enabled but it causes crashes in certain situations so it's choice between slightly blurry text and occasional crash. Firefox works well, it used to require an environment variable not sure if it still does. Chrome support still not there, scale is correct but text is blurry.

I haven't had any issues with display scaling using Fedora for quite some time.

I am odd. On Windows I use 2x scaling on a 4k screen. On Linux I go unscaled and just bump up the text size in editors and GTK/Qt apps.

I found that scaling killed performance for me on an old intel 6500U, so I bumped font sizes and icon sizes up and went unscaled. DrRacket is the only program that doesn't obey it currently. Even Emacs works fine.