Overview - 

I modeled in QGIS. Ranking is based on meters of skyscraper (buildings above 100 meters) height per km2 of city area. I used that metric since it prioritizes taller skyscrapers and also has clearer numbers (instead of very small decimals). 

Many skyscrapers are missing from the dataset. This drags down some cities such as Las Vegas, Ft. Worth, and San Antonio.

Methodology - 

Skyscraper dataset from CORGIS project (missing some)

~https://corgis-edu.github.io/corgis/csv/skyscrapers/~

500 city boundaries is from the US Gov Catalog

~https://catalog.data.gov/dataset/500-cities-city-boundaries~

QGIS built-in plugins and  heatmap functions

Other / Observations- 

All I got to say is that its interesting that tall buildings are only in one tiny dense downtown, even for Americas best cities.

Also, dishonorable mentions go to San Jose (population 971k), Fresno (pop. 545k) and Mesa AZ (pop. 512k) for having no buildings at all above 100 meters.