well because it's a good suggestion, but a horrible suggestion balance wise. It's also kinda obvious how little people actually are high agi characters, most people stayed with a balanced build anyway.
But there's still more than enough high agi builds (21 agi or
much higher) running around. Maybe moreso on NA than EU, I don't know, but a agi player in heavy armor having just as much effective weapon proficiency as my balanced-ish build in light to medium armor is ridiculous. I like the idea of a higher requirement on heavy/plate armors.
The sudden influx of "assassin" builds is also quite annoying after a while. A guy in liederhosen can run around behind a team and come up behind with a knockdown weapon... it gets annoying after a while. Or when a guy in heavy or plate can catch my archer ... - ah forget it. That's a whole other barrel of worm and maggot-ridden apples, and it's off topic.
*EDIT* And, I know it's really off topic here, but, has anyone actually seen Kaoklai upvote anything? lol