The numbers in the chart are for shopping center space alone. The US has closer to 40 sf of space per capita (Southern Florida has 74 sf/person!) Unfortunately the European numbers are distorted by this as a smaller percentage of retail is located in malls. A reasonable amount of shopping per person is probably more like 10 to 20 sf. Doesn't negate the overall thesis, but perhaps a bit sloppy.

Copenhagen's new subway is also driverless, with very frequent service. Also the trains, and thus the station platforms, can be shorter, thus simpler and less exprensive. Very smart and the way to go all around. Obviously these systems need to be grade separated. A very good thing, much faster, and it also avoids the issue of the significant hazard to cyclists that LRV tracks in the street represent.