Why is gid 100 USERS group bad to use?

I did not save the syntax to post here but I got a warning popup mentioning something about using the users group, which is gid 100, with the **insinuation** that I should not be using it. I think it may have been around the context of a RHEL 8/9 system which was using LDAP as the back end to manage user accounts on the system instead of /etc/passwd... but I am not sure. What is the current convention & best practice of making use of gid = 100 users group as it comes pre-defined in RHEL 8 and RHEL 9, and presumably still in RHEL 10 ? Is there a reason when not to use it?