I do not really know which part of the GNOME causes the problem so I decided to ask here instead of going to GitLab.
Font rendering with any fractional scale on my Fedora 41 Wayland happens to be very blurry. Below are screenshots with 150% fractional scaling via display settings vs 1.5 text scaling via GNOME Tweaks.
I’ve noticed this too with scaling set to 1.25. Interestingly, it only seems to affect labels in list boxes or popovers. Mostly obvious in gnome-control-center, and only in the hardware accelerated renderers (i.e. not cairo).