The EC is an American tradition and we should preserve it. The founders wanted this so, that small states have some say in who is elected and CA, TX, NY, and FL do not outvote everyone
The framers also wanted slavery, an appointed Senate, and for women to be property with no rights and we got rid of all three.
Those three things are morally wrong. Allowing all 50 states to decide an election, instead of 4 gigantic states (CA, TX, FL, and NY) is morally correct.
The state borders would be irrelevant in a national election. If it's a national office why does it matter where geographically in the country someone lives? The President can affect someone in Kansas as much as someone in NYC.
A vote would be a vote, a person would be a person. "People" in NYC wouldn't get more of a say than "people" in Kansas.