Earlier quoted context omitted.
That still doesn't explain why there's no gigabit FTTH in NYC, with its high average density. It sure as heck doesn't explain why there's no gigabit FTTH in Manhattan proper--by your reckoning the borough should have a residential density even higher than its overall average would suggest by virtue of Central Park taking up so much of the upper half.
High density doesn't eliminate millions of other reasons that a given city doesn't have it. It just provides a floor for cost competitiveness, and a major input into ROI. Even in Kansas City, google has stated they won't roll out FTTH to every neighborhood, even in the long term...and in the short term, they have focused on the neighborhoods with the fastest ROI. I'll let you guess whether the high density or the low…
Unless you're saying that urban and suburban America each lack FTTH for their own wholly unrelated reasons, an explanation that seems rather lacking in parsimony.