If it wasn't Every Man for Himself, it would be something else. PvPers always disdain this truth, but PvP is a side activity in World of Warcraft. The game is a PvE one. The balance is made for PvE encounters, trying to make most classes useful in a party or raid, and capable of overcoming PvE obstacles (and even at balancing that they fail).
The only way there would ever be balance in PvP is if every form of customization beyond cosmetic was removed. No racials, no classes, no specializations, everyone is the same, has access to the same gear and skills, there's no paper-rock-scissors class countering, and it all gets down to personal skill with the exact same toolkit everyone else in the match will be using.