The NBA offers more pathways for players to reach the league, including playing overseas or in alternative leagues like the G-League or Australia's NBL. Despite these options, the NCAA tournament remains a key platform for players to become basketball stars. Only 57 players have won both an NCAA championship and an NBA title, including legends like Bill Russell, Magic Johnson, and Michael Jordan. Recent additions to this list include Christian Braun and Connor Gillespie from the 2023 Denver Nuggets, and Al Horford, who won his first NBA championship with the Boston Celtics.
Source: https://www.si.com/college-basketball/how-many-players-have-won-the-ncaa-tournament-and-nba-finals