I agree, but the European apartments also typically have much more practical use of space. The U.S. condo market in particular seems aimed at single people or couples who want to have cocktail parties all the time, followed by retreating to their luxurious master bedroom suite for a romantic evening. Or at least imagine that they would, so are looking for a place that looks impressive for that use. The focus is on big, airy open spaces (open-plan living/dining/kitchen areas), plus a large master bedroom suite with attached master bathroom, walk-in closets, etc.

One reason Americans find it hard to imagine raising a family in an 900 sq ft (85 m^2) unit is that if you design it this way, it really isn't a lot of space for a family, or at least not space laid out in a useful way for a family. That much space would typically be only a 1-bd in SF or one of the newer NYC buildings (maybe even a studio). While in much of Europe it'd be a 2-bd, or 3-bd, and even compared to American 2-bds the space would be laid out more practically (e.g. less space devoted to those giant bathrooms and walk-in closets).