The NBA's gonna have a real problem on its hands when LeBron James retires ... so says Kwame Brown, who tells TMZ Sports the league isn't putting enough focus on the next generation of athletes -- like that one guy on the OKC Thunder.
We spoke with the former 2001 No. 1 overall pick at LAX this week about the current state of the Association ... and he pointed out the top teams in the Western Conference aren't getting nearly as much coverage as the Lakers due to the LeBron effect.