It's amazing to me that Blizzard spent 15 years with the PvP realms in such a broken state. It was only when they introduced "war mode" and the option to turn it off that people finally had some relief.

What finally made them address the problem was that many PvP realms had become 95% one faction and 5% the other faction. That meant that any PvP encounters were very one-sided, and they were also very rare, because the outnumbered faction just avoided any areas where they might be attacked.

Even if you lived for griefing, being on the dominant side in a 95% your-side realm sucked because there weren't enough victims to pick on.

I guess they wanted to make griefers happy because making the game fair for people who enjoyed PvP but didn't want to grief others would have been relatively easy.