To be clear, I don’t agree with the notion that the president requires immunity in order to be “undistracted” while being president.
I think that immunity for explicitly delineated powers makes sense purely from a logical point of view: the constitution says the president can do a thing, therefore a law saying they can’t do that thing is either unconstitutional, or doesn’t apply to the president.
If they’re impeached it wasn’t a valid use of their powers and they are potentially personally criminally liable.
I feel like it’s less traditional immunity and more an acknowledgement that the legislature can’t criminalize things in the constitution, and someone can’t be guilty of a crime under an unconstitutional law.
It’s the not-enumerated official acts bit that’s wonky to me.
I don’t think anything that trump did would even remotely fit under an enumerated power of the president, which are pretty clearly and narrowly defined. Nowhere does the constitution empower the president to futz about with elections. If Congress delegated that power to the president, then the president is acting in the bounds of a law they can break.