In Commander
Jund chooses Wrenn and Six, Urzas Saga, and Lurrus instead of Expressive Iteration to keep the gas flowing through the middle turns of the game
First of all, if your deck is based on doing good things with a sac outlet, your opponent probably wants to kill that outlet so that you cant do your thing anymore, but Cartel Aristocrat is very hard to kill so your engine protects itself
In an aggressive deck, this is likely to be more than enough to kill them off - and that's not accounting for any extra creatures you may have, any ramping you've done or spare mana you've created
Learn cards in Commander totally depends on your table
Right now, Push is not shining anymore, due mostly to unholy heat that replaced Fatal Push as the best removal of the format since it can deal with planeswalkers too