I have major concerns about them.
There are no checks performed so we have people stating they work in a certain area when it could be complete bollocks. An entire thread inviting questions to a person claiming to be a professional is very different to someone popping on a thread for a post or two and claiming to be x or y profession.
Even if the person is from a particular profession, they might be a shit Dr or SW or they might be a good one but they can only speak from their experience. LAs and CCGs vary.
Very personal and confidential information about patients/families are being disclosed without the knowledge or consent of that person.
It attracts trolls. Both those starting threads and those responding. There are sexual deviants already on MN without attracting more who want to ask questions about child sexual abuse or sex working.
Some of the people starting threads are clearly emotionally vulnerable.
The questions are often salacious and inappropriate. People being asked about worst experiences, highly contentious questions or just perverted ones.
I don't think a parenting site primarily used by women should host threads by e.g claimed sex workers talking about how they've wanted to be a sex worker since childhood because they love the sex so much and lolling about being paid to be publically humiliated by walking up and down streets with semen filled shoes on while other posters ask them about how sore their vagina gets..