It is both.
crfernald wrote:one or two messages per second limit.
The fix I added was precisely to limit chat to three messages per second (with a temporary burst of up to 5 messages allowed). I think that ought to be enough for the frequency problem. Do you find this is not the case, or is the problem, indeed, the lengths of the messages?
Think of it like this, if you need to sink a ship you can do it in several ways. You can hit many small chunks of ice until the hull is torn to shreds, hit several moderate iceburgs and crack the ships ribs, or hit one big iceburg and snap yourself in half.
The script Sarchi posted in Naowhut's thread doesn't seem to work as well now, but it still works to a degree. If you run a similar script with a larger text body and have it cycle faster, you crash the game just like before, no change.
A temporary burst of 5 messages is why your fix doesn't work, you can just compensate by spamming more data.
With a fixed limit of three you'll likely make it so that only the person running the script will crash, but we can't test that unless you actually implement it. If you limit both the message rate and char limit this problem will never arise again.
It's a simple matter of removing the possibility of abusing the area chat system vs fixing a vulnerability in the chat system against one script of several.
Edit: To address Valten, if you run a script that's short enough not you crash yourself out, but still enough to abuse the system, you can crash other people. It's mainly trial and error and the sweet spot is rather wide. I'd imagine it is also dependent on your system and client.