If the elements effect your spell damage that greatly then why bother having Intelligence in the game?

Why can't MMOs just let me focus one two stats like Int/Mind. No, now I have to focus on 3 Attribute stats and 6 Elemental stats to be an effective wizard? I like fire, I would put more points into that if anything, but now what happens if they release an entire dungeon and all mobs are fire based? Sure I could use my other spells, but now they suck worse than before.