Free trade should be allowed, restricting it is only going to kill the game. People are already leaving / considering leaving.
Bitching about RMT spam is just making it worst, you are going to have to live with them they are not going anywhere.
But you shouldnt ■■■■ over everyone who plays trying to eradicate RMT by limiting trade to practically non existant. The game should have open trade 100%, whether it is open or not RMT is going to continue.