You do realize that the term “State” and not “Province” is used to describe each State?
Do you understand why? Because the word State means “country”. We are fifty separate countries united by a Constitution. Each candidate for the Presidency of this union of countries is elected by fifty separate countries. Each one of those countries deserves to have the right to have a voice in the election of their President.
That is why the Electoral College is important. Each country (State) in the union deserves to have a solid, form voice. Not just the thirty biggest metropolitan areas.
Just look at what happened to the senate when we started electing senators by popular vote. In most states, the cities elect the senator.