The main Arch build of mold is at 1.4.0: https://archlinux.org/packages/community/x86_64/mold/
while the ARM official build is still at 1.0.1: https://archlinuxarm.org/packages/aarch64/mold
The mold-git AUR package builds fine with the same dependencies as the official build, so I don't think there's an issue with them.