re: Aaron Judge vs NBA rookies

Mainly because 1 player doesn't make a huge difference in MLB. You also have that player (say Harper) standing around most of the game or sitting in the dugout waiting to bat. MLB could promote pitchers the way the NFL promotes QB's I guess, but that would be it.
It is much easier to watch a basketball game for 2 and a half hours and see James, Westbrook, Harden, Durant, Curry, etc for 90% of the game vs watching MLB and seeing Harper for 50% of it.