My understanding is the basis for the numbers are (1) infrastructure improvements, and (2) opportunity cost assuming someone would develop to the highest use imaginable.
Of course, the infrastructure is necessary for any development. As
DeGrozz noted, the area is a toxic dump, and as the former land owners out repeatedly reminded us, the area never had any sewer service, among other things, which the city refused to ever build and then used as an excuse to take their land via eminent domain.
As for the opportunity cost, LOL. Like there has ever been a big development in New York, especially on land owned by the government, that isn't a product of favors and offsets. If the stadium gets scuttled, the new deal will be no better. And the idea this is comparable to Buffalo is to laugh.