As stated in the past, blizzard solely is at fault for this. RPPVP was the only non-full realm type for PVP at release, and as a result waves of non-RPers overflowed onto the server for lack of anywhere else with room.
Blizzard could take some time to actually crack down on those actively ruining the RP experience on the server, answering all of the reports they get with an iron fist. They seem to be doing nothing of the sort, sadly.