Last week the National Basketball Association loosened its decade-old restriction on drafting elite players directly from high school. The president of the G League, the NBA’s developmental division, announced it will allow franchises to recruit 18-year-old players at an annual salary of $125,000. After a year, they can be promoted to the big league. Starting with the 2019-20 season, the revision will let the nation’s best young players pass over college on their way to the pros.

The rule change is a response to criticism...