KG's peak at Minnesota was much better than Webber's.
Similar scoring (KG was more efficient there though too) and passing, much better defense and rebounding. Makes a big difference when your peak is MVP and if your peak was merely all-nba.
much better is a stretch. Webber was a better and more varied offensive player. Much higher peak ppg, more post moves, and a longer range on the jump shot. Webber was a much better ball handler and they were both excellent passers (Webber actually has a better career AST%). KG was obviously a better rebounder (though some of that is who they played with and Webber was actually a better offensive rebounder) and a significantly better defensive player overall (though Webber was a pretty good shot blocker and his man defense was always underrated). KG was/is better but their peaks aren't so far off that a comparison is silly.
Not a stretch at all. The PPG difference is a few points which is mostly explained by a much faster pace and slightly higher usage by Webber. Meanwhile KG had superior efficiency at their best, gave him a higher ORTG, PER, ARPM, win shares, every way you can measure it.
KG had a higher assist percentage at their peaks too, his career is lower because he's still playing as an offensive role player. Also KG was a better offensive rebounder at their peaks, Webber had right around 7 during his KG was at around 9. KG has just played longer his offensive rebounding declined as he aged and played more seasons and minutes as an older player (plus coaching wise Doc had him bail on it to play D).
Webber had a better low post game, but KG had his killer face up game in the high post and an underrated post game himself.
So yeah KG had a much better peak that was also longer (I was really sad for Webber when he blew his knee right in the middle of his), I think the difference between MVP caliber peak and an all-nba talent is significant one.