Not quite. The office of the President already had legal immunity for official acts, the only thing that SC ruling did was reiterate that and also stymie efforts to pursue a legal case against him by buying more time for him to get re-elected. That last part came from having to refer a case to the SC if there was a question over whether or not something was “official”. If we had a functional SC that wasn’t assisting the Executive, it wouldn’t have been a big deal.

Unless the American people vote out the majority of politicians who want to protect Trump to further their own agendas, there will continue to be an evisceration of decorum. He has no true legal protection, just political ones.