This is true. I don't live too far from de Blasio, and his house is nothing special. Also, keep in mind that property values in Park Slope (including the area of Park Slope where he lives) have skyrocketed in the past decade or so - depending on when they moved in, it's likely they paid much, much less than $1.1 million. I know people in the area who bought places for ~100k that are now worth $2m+.
Agree. I know some who moved into Park Slope when it was similar to Crown Heights.