Obviously you have no recollection of what kind of player Carmelo was at 23 years old. You want to talk about selfish stat stuffer who never passed the ball, and someone that was a consciencious objector to playing defense... Yep... Maybe Melo is better than Harden right this second on both ends, but in 5 more years(barring injury) I think Harden will be a much more well rounded basketball player, and affect winning in a much more productive manner with his playmaking, and passing ability. Also, those Denver Nuggets teams from 05 to 09 (comparable to Hardens upcoming Rockets years) he had a very good lineup that was essentially built around him. Houston has a roster filled with first time starters, and rookies. Hardly the kind of veteran help Billups, Martin, and Nene brought those Nuggets teams.
Melo led the Nuggets to the Playoffs in his rookie year. That's after he won the NCAA title as a 18 year old. At TWENTY ONE years of age, Melo won the Northwest Division averaged more points than Harden did this year, while playing less minutes. He also shot 48% compared to Harden's 44%. He averaged less turnovers. Harden averages more assists, which is understandable considering he's a SG that basically plays PG in Houston. At 23, Melo was shooting almost 50% and grabbing 7.4 boards a game.
Because he was on good teams completely built around him being the main scoring option. Take Melo off of any of those teams, and they are still very close to if not playoff teams. Take Harden off the Rockets, and they are lucky to get 35 wins. Melo has always been one of the best scorers to ever be put on this planet. Nobody is denying that. Harden isn't quite that gifted offensively, but he has the ability to do much more than just drop 50 which has been Melo's role in prior years. In 5 years, I have no doubt that Harden will be a better well rounded player than Melo currently is. He might never be the scorer Melo is, but he will be just as important, if not more to his team winning.