I'm not sure it's fair to say that he doesn't care. He's injured and has been injured. The NBA, ESPN, Duke basketball and many others in the media all share blame in making this kid bigger than life before it was time. One of the major components to being a super star pro athlete is being available to play. He spent one year in college, got hurt. His rookie year in the NBA, got hurt and suffered yet another lower leg injury before the current season and isn't healing very fast. I hate to call a guy a bust due to injury, when he's played, he's played very well. He just can't stay healthy.
Some suspect he may be playing the injury card to get himself out of New Orleans, which would be very sad.
If you recall, Joel Embiid's career kind of started out the same way. Embiid was drafted in the 2014 draft, and missed all of his first two seasons with the Sixers. He played only 31 games in the 2016-17 season and never any back to backs. Since then though he's been "relatively" healthy, playing 63-64-51 and 51 games the next 4 seasons.