The question becomes what if the President then uses their power to jail/execute political rivals? How would you rule that as unofficial? Tons of dictators jail rivals on the “official” business of maintaining order or peace or some other nebulous term. The presidents role to enforce law is so broad that it can be used to justify almost any act.

> there is also no way to prove it’s “unofficial,” because any conversation the president has with their military advisers (where, for instance, the president tells them why they want a particular person assassinated) is official and cannot be used against them.

> Trump murdering his business partner at a dinner because they had a fallout is pretty clearly unofficial

Why? The majority said In dividing official from unofficial conduct, courts may not inquire into the President’s motives. Nor may courts deem an action unofficial merely because it allegedly violates a generally applicable law.[1]

[1] https://www.supremecourt.gov/opinions/23pdf/23-939_e2pg.pdf

You listed two extremes to demonstrate the difference, which is fine, but what about the example of Trump encouraging insurrection? It seems just a teeny bit relevant here, given that it is what prompted the case in the first place. And insurrection is definitely related to governing, so you can't discard it from consideration just because it's nothing like murdering a business partner. He could claim that an illegal decision was about to be made and so he had to use his executive authority to counteract it. That sounds like an official duty to me.

Uh, you're missing the fact that his business partner is a danger to national security. The motives are irrelevant.