If you walk into a franchise sandwich shop and order a sandwich, the sandwich maker builds the sandwich per the instructions in the company manual. There is no room for interpretation or creativity: build the sandwich per the company’s instructions or you are fired. The result is that the sandwiches are consistent and meet the customers’ expectations. It doesn’t matter who builds the sandwich, the result will always be the same.
The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.
If we had a limited federal government as outlined in the Constitution, you wouldn’t care who was President because that office wouldn’t have 1/10 the power it has now. It would make no difference in your life.
The Tenth Amendment: better than the alternative.