It's just that it is unexpected, so people have lots of characters that no longer work the way they expected or intended them to. That is a real problem. If you attack a red, you should not be allowed to run to town and be safe. No way, no how. The guards at the gate should tell you 'Finish your business first bounty hunter', or something similar. Plus, there is always the issue of area-effect griefing to worry about. People really do run around oranges or greys on blue characters, just for the sole purpose of giving counts, or to utilize guard-whacking (with their very own mount if they can as if that makes any sense). Yes, people are that lame. That is why they used to have different area-effect rules for this ruleset here on this shard. It's more of a modified siege perilous ruleset in many ways, since they only have one facet, and it's supposed to be kind of hardcore. There are plenty of situations on the shard, with the current coding mechanics, where you have no chance whatsoever to kill someone 1v1 without some type of area-effect damage (Hider-healers in town, just to mention one of the most obvious).
On the other side of things, probably more PVP has happened today in dungeons than likely all of last year combined. If they keep at it, building code to switch things up with the monsters all the time to keep people finding new spawns, then that could certainly be a great thing. They just have to make sure it doesn't quickly go stale.