Meanwhile Fedora 40 installs like a champ from the default aarch64 iso with just a warning about EFI variables (which is expected since tow-boot is not really providing a complete uefi environment).
I suspect it’s probably some voodoo formula to manage the device trees. Those github flakes to generate imsges are pulling an entire root tarball from hydra so I’m assuming there is something done there that is not obvious.