Often, when people evaluate capitalism, they evaluate a system that exists on Earth. When they evaluate communism, they are talking about a non-existent Utopia. What exists on Earth, with all of its problems and shortcomings, is always going to fail miserably when compared to a Utopia. The very attempt to achieve the utopian goals of communism requires the ruthless suppression of the individual and an attack on any institution that might compromise the loyalty of the individual to the state. That's why one of the first orders of business for communism, and those who support its ideas, is the attack on religion and the family.
PS: Ask your son to listen for the words "think" and "feel". Their use generally defines whether one is talking to a lib or a conservative. It works almost every time on talk shows. I bet it will be the same on campus also.