The NBA has rules and some of them are occasionally enforced. Making sure the rulebook definition of traveling is strictly adhered to is not at the top of the priority list, especially for superstars.
That’s how you get stuff like this: LeBron James taking a nice little walk before knocking down a big shot.
If he had traveled one more time, the officials may have called something. Basketball is famous of its “three strikes and you’re out” policy.