Safety.

All the cars mentioned have adequate HP and torque to tow 500-700 lbs. But their short wheel bases, minimalistic brakes, spindly chassis and light weights make them unsuitable to safely tow a 16+ foot catamaran due to the windage of the load. (A small, compact load of similar weight may be a different story.) I've towed a lot of boats and other trailers of various shapes and sizes over the years. You do not want the tail wagging the dog!