So for Dantley, his successful offense often came at the expense of his teammates.
Did you look at Dantley's roster in Utah? I don't think anyone can win with Ben Poquette and Darrell Griffith (who is much more the "empty calorie" type) in some of those years. Utah during the Dantley era had been rumored to move to Minneapolis before Larry Miller bought the team in the mid 80's and because of financial problems started playing games in Vegas to get some gate (Kareem set the points record in a "road" game in Vegas against the Jazz, for example). It was not a very well run organization until Miller bought them.
Utah probably underachieved some at the end of the Dantley run there but I'd argue it was a product of having a roster that was reasonably flawed even for years into the Malone-Stockton era and, at the beginning of the Malone-Stockton era, was quite raw.