That sentence doesn't even make sense, considering that
Duncan is better than Kobe by every objective measure.
Awards: More MVPs, more 2nd place MVP finishes, more career MVP vote shares, more Finals MVPs
Ringz: Same # of rings, more rings as the most important player on the team, fewer playoff misses and 1st-round exits
Advanced stats: Better career PER, better career win shares, better career box plus/minus, better career Value Over Replacement
Intangibles: better teammate, driven fewer stars/coaches out of town, never quit in a game to make a point
Can't make an objective argument for Kobe that's not focused around "I don't care how many shots he misses as long as he scores lots of points" or just screams, "but I'm a Kobe Stan!!!!!"