Thanks for reporting this. We’re currently working on updating the packaging for Arch as well as fixing various checks that would fail specifically on Arch. There are some details in this topic: Updates to snapd package on Arch
If you’re willing to experiment, can you pull the PKGBUILD from this review: https://github.com/snapcore/snapd/pull/4174 and try makepkg --nocheck -i? This will build and install snapd-git package. You may need to systemctl stop snapd snapd.socket before installing the package and systemctl daemon-reload after.
BTW. is this the node-red-amd64 node-red snap you’re using?