Even wirhout much info, it still becomes easier to dox if you have the person’s location.

I mean they could travel to some other library, it doesn’t need to be the one closest to where they live (though ofc it would still locate the general region/city).

I used to be a member of a closed torrent site that operated on this principle. You got a handful of invites you could share (active seeders got more), but you were sorta responsible for the people you invited (your username was visible to all other users on the invitee’s profile) and could face repercussions if the invitee broke the rules.