Zone defense and the 3 seconds rule have much more to do with this. Zone is much more common in college and seems to explain the stats because 2-3 gives up the high post and 3s on the wing to protect the paint.
It's harder to run zone in the NBA for many reasons, not the least of which even a bad NBA shooter is a pretty good shooter when they have room to get a shot off. Given the shot-heavy nature of today's game, you'd be hard-pressed to pull off zone against a good chunk of the league.
Yes, I just stated the fact that zone defense is much more common in college basketball and that it might explain the disparity in shooting percentages at different distances.
Zone was forbidden in the NBA for a long time and, as you said, even now it doesn't make much sense to run it at this level because of talent, 3 seconds rule and the distance of the 3 point line.