Everyone thinks that USA Basketball forced the IOC's hand to allow professional basketball players at the Olympics because our amateur teams could no longer dominate elite international teams, and was heavily criticized at the time for the Dream Team's inclusion in the 92 games. The truth is that USA Basketball fought FIBA and the IOC for years, trying to keep the amateur status for international basketball. When the decision was made to include professional athletes in the Olympics, of course we sent our best, and that original Dream Team was head and shoulders above everybody else.
To answer your question, the only international basketball competition most American sports fans care about is the Olympics. No one cares about the FIBA World Cup, especially enough to disrupt the NBA and/or NCAA Basketball seasons to field a team. Hoops fans in this county value NCAA Tournament Championships and NBA Championships above all other basketball titles. I can guarantee you that well over 99% of basketball fans in this country had no idea the FIBA World Cup was happening, or even that it was a thing. I didn't until you started posting about it.