While I can understand you're not wanting to get PM's that speak of others in negative ways, I think there is also a good side to PM's.
PM's can help those that are too shy, scared or lack confidence to post something... so they share their situation with a trusted member/friend using PMs. It can even be a "stepping stone" to posting.... kind of like practicing posting but on a safer feeling-smaller scale.
Some of us have endured ridicule and invalidation IRL-- all our lives-- so PM's with a safe person can mean a lot to us.
I hope you can see the good side of them and I hope that they will never be discontinued..
AS--
mandy