There's no way a single person is qualified to teach all those subjects. Even if they bring in all sorts of different teachers, it still prevents people from getting social education and learning to live in the world.
Plenty of ways to learn social skills: church, youth sports, scouting, interacting with other home schooled kids,
even going outside to play with other neighborhood kids after they come home from school. Nah, strike that last one. I don't think kids just go outside to have unstructured fun anymore.