Also, each state was guaranteed a “republican form of government.” This pact changes the state into a Hugo Chavez style democracy, where 51% dictate to the 49%.
While the NPV is a horrid corruption, it doesn’t violate Article II or Article IV. Scotus loves democracy and elevated voting to a fundamental right.
I’ve often made the same argument that you did in your post 9 and surprisingly many people here disagree with us.