That's on the mark! It's also pretty clear that manufacturers did want to utilize this as it reduces tooling costs a lot. But, in attempts to increase fuel efficiency/reduce weight(cost) they lost rigidity and went to unibody.
Composite & battery technology are enabling these types of designs again.
As for the lead comment, it's true that the exact same 'skateboard' isn't going to perform, but keep the board and swap 'trucks & wheels'. There's your sports car cum minivan.
It's about the chassis not the rolling
The thing is companies don't really like using modular chassis like ladders anymore is because anything that can't use the roof for structural support is heavy and flexes like mad.