Such gerrymandering was possible only because New York, and especially Brooklyn, contains dramatic juxtapositions of prosperity and poverty, juxtapositions highlighted by decades of recent gentrification, which has had little impact on entrenched poverty in housing projects.
Indeed, a map (below) from WNYC via The Local points out such juxtapositions.
According to The Local:
With a average income of $9,001, the second-poorest census tract in the city is in Fort Greene, WNYC reported. The Ingersoll and Walt Whitman Houses are inside that tract, the darkest red area on the displayed map.
...Two tracts over from Ingersoll and Whitman, No. 183 has an average income of $83,105.
I'd also point out that the WNYC map points out significant differences among census tracts bordering the Brooklyn Navy Yard (tract 543).
For example, census tract 21, including DUMBO, has a median income of $163,147 and, consequently, a very low unemployment rate.
By contrast, census tract has a median income of $18,702 and, consequently, a very high unemployment rate.
Guess which one was appended to tract 543 to create a Targeted Employment Area?
The WNYC map