Adding amendments went out of favor when the federal government misinterpreted the commerce clause so hard that it completely flipped the government power structure; the modern hip way to govern now is to use unelected buercratic committees to determine people's fundamental rights
Congress keeps ceding more of its power to the executive, since it can't seem to accomplish much of anything any more. It does allow stuff to get done, but the only oversight is whatever the voters decide to do every four years.
