md5sum has never worked on a crypt remote. At some point rclone became a bit more consistent about showing empty (meaning I don’t have an md5sum for this file) or “UNSUPPORTED” meaning no files have md5sums on this remote.
I was going off of another thread where cryptcheck was reporting “X hashes could not be checked”. The recommendation was to find files that were missing a hash. Now that I reread the post I see the recommendation was to check for a sha1sum and not a md5sum. Unfortunately I see the same output with sha1sum, “UNSUPPORTED”.