KG also had an All-Star Wally Szerbiack in the early 2000s in his team, as well as Chauncey Billups who would become the go-to player for the Pistons after he left.
But let's concentrate on the le teams because this is what it comes down to. KG won after two other veterans elite scorers decided to sacrifice their paycheck to team up with him. The "perfectly" tailored team that Dirk required to win, against an arguably more difficult opposition, was really an athletic defensive center and some quite regular players around him (Kidd and Marion were far, far from their peak, Peja on his last legs, and JET who never made an All-Star team was the most dependable second scorer).
Essentially the team that Dirk required is much more easily assembled in the NBA that the team that KG required. You can get defensive, hustle players much more easily than you can get elite scorers - that is the skill of which there is a shortage in the market and that is why those players usually get max contracts. This is what it really comes down to when you build around a superstar: if he is an all-world scorer, everything is much easier.
If this were baseball or European soccer where you can stash all kinds of stars together without financial repercussions, than maybe KG becomes more valuable. But it's not what the NBA is or has been. It's a league where your franchise player needs to be an elite scorer, and if not it makes it more difficult to build a championship team. Dirk was that, along with Shaq, Timmy, and Kobe. KG was never in that picture. A healthy T-Mac and Yao probably overtake him as well.
And this is where I'll stop because KG v. Dirk arguments have been overdone here.