I think the more important factor is that it eats runway and takes longer to reach safe speeds. If there is a problem at rotation you want as much runway available as possible. If you delay rotation not only are you further down the runway before "really rotating", but you're traveling faster. A 10-knot increase in speed means 20% more energy to disipate. And you're even further above the brake's certified performace. And you've dawdled in getting to safe climb speeds; you accelerate more slowly rolling than flying.

Edit: Actually, that probably doesn't even come into it. Not a pilot, but don't imagine "barely rotate so the nosewheel is in the air but still have negative angle of attack so no lift" is very easy, or very stable if possible. Even if you could do it, you'd risk slamming the nosewheel back into the runway.