> Sedans, coupes, or anything with less mass will be ... more capable
I beg to differ. They may be safer and more efficient, but they get those advantages by trading off cargo and passenger space. A crossover can carry a heck of a lot more than a sedan and still fit 5 people - hence why it's the "local maximum."
SUVs and crossovers actually tend to have less useable interior area than vans or station wagons. Another advantage of vans and station wagons is that they're built on chassis similar to sedans which allow you to maintain a low center of gravity for better handling.