Even the one graph they provide is more or less incomprehensible. What would be useful to see is land prices in inner urban areas, average lived population density, and comparative migration patterns for young adult populations (ideally taking into account long term lifestyle pattern trends).
My general take:
Places like NYC, SF, and Chicago are definitely growing, but not at some particularly spectacular rate; IIRC it's at pace with US population growth as a whole. Instead the areas with the highest population growth have been the sun belt for the past decade, which is hardly the "smart" urban growth that people go nuts over.
The demographics, however, are changing in a much more meaningful way. Gentrification will continue and accelerate. Not everyone will live in the city: instead it will be a professional ruling class working in government, finance, law, technology, and business (and their associated servants), with everyone else relegated to the decaying suburbs.
So if you want to see the future, look at Paris.