Well f*ck me, RHEL 9 finally got rid of NIS. I think I knew this was coming but that was so far in the future, I had plenty of now problems to deal with. They are right, NIS is not at all secure for user auth. Great. I don't use NIS for that anymore. I use NIS for groups, netgroups, and automount maps, especially automount maps. I'm not worried about security for those. Might be time to finally develop a replacement to those bits of NIS and retire NIS like I've been contemplating.
@kalpa@thaodan Thanks. I did not know that was a thing. I'll add that to the things I check out. This project is literally something that sprang out of some work I was doing this afternoon so there has been zero work or planning done so far. It is proving to be a potentially very interesting project so i have that going for me.