Of course you can stack em up and have 20+++ floors along just the shortest of the 3 dimensions of just one of the 'legs'. But that is NOT how the city was drawn and depicted in either the TV series of DYRL. Thats my point.
To have a livable city of 50k and not cubeville (look, i am not arguing that you cannot stuff 500,000 people in there if they live like submariners in a WW2 Imperial Japanese Submarine), you need a LOT more space than even the _entire_ SDF can provide.