“The Government of Cuba does not recognize the U.S. nationality of U.S. citizens who are Cuban-born or are the children of Cuban parents.”
Am I missing why we should care what the government of Cuba has to say, or why US law or election law should hinge on irrelevant statements coming out of Cuba?
What you are missing is a standard of international law that whether the government from which a citizen originates recognizes the idea of dual sovereignty. I actually agree with Cuba here in that a person who desires to become a naturalized American citizen must first renounce citizenship and allegiance to the land of their birth.