AppImages depend on fuse2, which is unmaintained and depends on a SUID root binary. For this reason, fuse2 support is removed by default. It’s strongly recommended that you find alternative mechanisms to install your applications (Flatpak, Distrobox, etc.). If you can’t find an alternative and still need fuse2, you can add it back by layering something that depends on it.
why not remove appimage support from fedora
A better option would be to improve appimage support in Fedora. Some packagers provide an appimage but not a flatpak nor an rpm. Removing appimage support would eliminate the additional source of useful software.
I have one tool I use regularly that used to be available in rpm but for the past couple years has only been distributed in appimage format. Seemingly due to the rapid changes that occur with fedora’s development schedule.