That is true. Numbers alone barely make the grade in comparing things. The 6.0 that was in the 1500's is not the same engine as the 6.0 L96 that has been put in the 2500's for several years now. And just because the 6.2 Eco has higher HP and Torque numbers does not mean it is in the same class as a L96 6.0. They have different designs and different target markets. And the L96 is just about the most bullet proof, proven engine that GM has in its stable right now.
If the 6.2 Eco was the base gasoline engine in the 2500, it could cause GM's primary customers for that vehicle, commercial users, to jump ship. One example, very few if any commercial users are going to be tied to premium fuel only, that is the recommended fuel for the 6.2 Eco. And the daily grind that most commercial pickups undergo, there is no evidence that the 6.2L has the stamina to deal with. The L96 has a track record of typically running well past 300,000 miles in work environments with no major repairs or problems. And it can use anything at the pump but diesel. Every ethanol grade in sight and regular or premium varieties.
And the L96 6.0L won the Ike Gauntlet pull test in a 2500. And did it with 13,000 lb of trailer, 3 people on board, and 500 lb in the bed. And in that test, it was at a higher combination gross weight than the competition. It put a 6.4 in a Ram 2500 with an 8 speed to shame.