I don't usually subscribe to it, but I do in this case, and it's not really anything negative about Durant, he's a fantastic, almost un-guardable player. It's between him and LeBron for best player in the world. But this Golden State team is different. Their system is unique and they feature maybe the most unique superstar in NBA history in Steph Curry. But, when you throw Durant in the mix they become more like every other team in the NBA, just that their best player is better than almost everyone else, but it's still just the same stuff as everyone else.
What makes GS so great is not only how they shoot, but the movement they utilize between Curry and Thompson, and the passing/play-making of Green. it's so unique in the current NBA. When you throw Durant in there, the movement slows down considerably and what makes, especially Curry and Green, them so great gets minimized.
Are they more talented with Durant? Absolutely. Are they better? I'm not so sure.