I knew when everyone was like NO YEAH TOTALLY GET IT last time it was a lie. I'm not saying my ideas about this are hard and fast, but no one else is insisting otherwise so this is kind of how I've been picturing a crosssection
That is the Eiffel tower obvs, the little pink dots are people for scale, and theres a bigger black dot near one on the bottom layer that is supposed to be a car. The amount of layers is modular, but where population is most dense I've been assuming is closest to that tightest, with the car section. The upper limits might be greater than this, but prob not by much.
But again, this is just...me making stuff up. If anyone else thought totally differently, then maybe its totally different. ¯\_(ツ)_/¯