Every State has a say in the operation of the union of 50 individual states we call the "United"  States. That is why each state has an equal number of Senators, regardless of their population. The House of Representatives is porportional to each state's population, thus protecting the popular vote as well as the individual State's interests.  We are NOT one big country, we are a federation of 50 Individual States, each with their own unique character.  Eliminating the Electoral College effectively nullifies each states' individual unique needs in favor of a few major metropolitan areas of immense population density.....BAD IDEA! 

For more information on this, check out this article from the 10th Amendment Center https://tenthamendmentcenter.com/2019/03/31/constitution-101-the-electoral-college/