helps users of paid relays, which i am one
so, full auth support makes it easier for me to do that... i still don't get full use of the filter.nostr.wine because i have to prod nostrudel to do it, it can do it, but it's still not following the protocol by doing it automatically for me
and there will never be private relay clusters for business use cases without auth on the clients and none of the funders seem to see it as a priority, thus the woeful state of it
yes, auth helps a lot of things... and privacy is one of them if the relay is trustworthy