I'm not sure I agree. In Aotearoa, a tiny country where government is fully integrated across the whole country, balancing representation according to the popular vote makes sense. But when electing a head of state in a federal system, where state governance is functionally independent in many ways? Does proportional representation makes sense in such an election?

My 2 cents for pro-democracy campaigners in the US is look into Single Transferable Vote systems. For elections at all levels of government, but particularly for Congress and the Presidency. Breaking the centre-right/ hard-right duopoly over electoral politics seems much more urgent than making sure whichever right-wing candidate wins the popular vote gets the President chair.