In addition to load management (players and teams do have millions invested in their ability to play in the NBA season) there's also a new brand of image management culture that's come with social media. Players aren't willing to risk looking silly or bad - perhaps because they have millions invested in their personal brand. I don't think the players you mentioned would like getting ejected from an elimination game like Luka did, for example, and that's really not that bad. Established stars don't participate in the dunk contest during the NBA All-Star break, all-star game is boring af nowadays - it's all around