Because Austin, TX has a very small and quaint downtown district with big, wide sidewalks and lots of extra concrete space in the roadways and ample gaps between storefronts and pedestrian walkways. Downtown BK has none of that.
"Ample gaps" means walking and cycling FURTHER (often across paved, dangerous, parking lots) to get to your destination. American cities are built for cars, not for people.
You do realise that for most of New York's history, when its construction was most productive, we had no real urban planning? If anything, the abundance and diversity of spaces in Brooklyn should make it easier to deregulate where childcare can be provided.