I have not checked with OpenBSD 7.9, but as of 7.8 it did not support --exclude or -z. But outside of that openrsync works great.
(EDIT: --exclude is now supported on 7.9. Not sure when that was added, nice!)
But seems avoiding "slop" is getting very hard. I saw postfix now has a bit of AI code in it.
https://mastodon.sdf.org/@mrmasterkeyboard@mastodon.social/1...