Darrell Walker complained about his situation after he started trying to land a college head coaching job, and could not, "Didn't I coach at the highest level?" What he said was true, but that was not exactly an argument in his favor.
In the first place, he won only a third of his games in the NBA. In other words, he was a loser there. In the second place, the college game is substantially different from the pro game. In the NBA there is no recruiting. And, evidently, there is not much in the way of defense. There are egos in college ball, but not nearly what there are in the pros. And the pro game is 100% entertainment. Even if they lose, the players still make a jillion dollars, so the motivation factor is entirely different.
No, being an NBA coach is not an overly strong argument for being a successful college coach. But Walker took a D2 stop in Atlanta and won there, and after that he could make at least a plausible argument that he could coach in college.