https://www.supremecourt.gov/opinions/23pdf/23-939_e2pg.pdf
> The president is immune to prosecution for any crime committed in office
That's a misreading of the SC decision. If he walks down the street and murders someone, unless he can make a case that it was an official act, then he wouldn't have immunity. He'd need to demonstrate that he has the Constitutional authority to murder people on the street, and he doesn't, so it wouldn't be an official act and he wouldn't have any immunity.
How about not on the street, but in a boat in international waters? Or, how about on the street, but they were believed to be carrying drugs?
ok, so we managed to get a decision that the president wan't immune from having to pay out in a civil suit related to the molestation of a woman from before he even became a politician. but part of the problem here is the blurring of the personal and the official. should the president be liable for overtly violating the constitution 'while performing official acts'. Is interfering in the state's right to hold their own elections an official act? is instructing the military to order someone in cold blood an official act? does pursuing a series of novel legal interpretations imply that he was violating the law or not? is accepting money in exchange for a presidential pardon an official act?
whether or not you believe this is a pass from the Supreme Court, it opens up a whole new unexplored space of lack of culpability.
But the state can manufacture any excuse to formulate an "official act"