Food for thought:
One issue with removing "undesirable items" from the PAB is what shall one do with those items? Trash them? Obviously, no participant want's to store (keep) them. One H-Mer's trash is another's treasure.
The items were probably offered, in the PAB, in the good faith hope that someone could put them to use.
My idea is to take any "undesirable item" out of the PAB and offer it in a "Trading Post" thread, free for the price of shipping.
I think that would be the best distribution of the "undesirable items" and support a basic tenet of the PAB.
Adopting that idea would accomplish many objectives. It would clean-up the contents, and reduce weight, of the PAB. It would offer the item(s) to the widest audience of members, which is the best chance of finding the item a new home. It would potentially solve any regret about trashing the item(s) if offered for maybe 6 months or a year. After the time period is elapsed, if not claimed, mark the thread "GONE" and dispose of the item as you wish. Any PAB participant could take the action, as long as they are willing to be responsible for listing the item in the "Trading Post" and follow through.
The Achilles heal may be that the process would have to be documented in the Rules and it's clear that following the Rules is inconsistent, at best.