@nightpool it was definitely discussed, I could dig it up in the SocialCG archives
A number of folks from the SocialWG were pushing for it pretty hard but the response we got were "we have this CW system and people already like it, we like that it's a single field you can just fill in"
I remember thinking, okay, maybe I'm wrong, maybe this is working alright in practice. But in the SocialWG (this is before we wrapped it up) alarms were raised about a single sensitive flag.