NYC is quite challenging to develop. For the story of some of those units in Brooklyn you're talking about, see https://en.wikipedia.org/wiki/Pacific_Park,_Brooklyn
It was bound to be complicated, and it's worth noting that it got built anyways. I've lived walking distance from the neighborhood in question for 17 years, and that project has nothing to do with a developer wanting to put up a regular old high rise rental apartment building or three, which seems to happen nearly daily around here. The Fulton/Flatbush corridors have been transformed literally in a matter of months.
1. https://en.wikipedia.org/wiki/List_of_tallest_buildings_in_B...