To have these loops on a public chat forum is extremely anti-social and against friendly integration and member relationship. The presence of these loops is offensive to most ordinary forum members.
The formation of a restricted topic specific loop is more than adequate. How the moderator then determines the valid interest level of an applicant to join is beyond belief.
I propose that Private and Hidden loops be discontinued and just retain Limited where the moderator can limit entrance to those applicants he/she feels justified. The loop heading would make it obvious what topic the loop deals with.