This just still isn’t fixed. It “works” if Xorg happen to run as root (or has CAP_SYS_ADMIN which is essentially root, not sure for the “exact” requirement) but distros and display managers will try to avoid this where possible for security reasons – with nvidia at most they give the user access to /dev/nvidia* through video group or other methods (this /used/ to be enough to set fan speed, but not anymore).
I don’t use OpenSUSE or Fedora to confirm what they do, but GDM normally does not attempt to run Xorg as root anywhere anymore (so, can’t change fan speed), while I don’t think(?) LightDM has support for rootless Xorg yet (sddm gained support this year, but distros may not necessarily be using that yet).
modeset=1 may (depending on distro) cause GDM to use wayland until select a Xorg session, setting fan speed also doesn’t work on wayland so it may have been related to your previous issues… but that’s not related to this one.