In 2012, Kentucky won a national championship with a roster headlined by first-year stars Anthony Davis, Michael Kidd-Gilchrist and Marquis Teague. Three years later, Duke followed more or less that same path, with Jahlil Okafor, Justise Winslow and Tyus Jones.
The NBA eligibility rules that made those Wildcats and Blue Devils teams possible are still with us. One-and-done is still here, as demonstrated most recently by players like Brandon Miller, Jarace Walker and Jalen Hood-Schifino. The most talented 18-year-old players in the world are still required to play one more year somewhere other than the NBA before they're eligible for the draft.