I use KDE Plasma 5.27 (6 with many improvements is around the corner) on Wayland and fractional scaling is handled very well, nothing is blurry, no hacks required. If KDE recognizes an app that is not Wayland compatible (like most Electron apps), it will just run it in X11 mode (there's a setting for that, enabled by default).
I'm using Wayland and Gnome set to a fractional scaling factor to write this, and none of the apps I use regularly are blurry although I have to pass command-line arguments to Chrome and had to compile Emacs from source code to achieve that.
See the screenshot of my settings: https://imgur.com/a/VQHD5vT