...a broker with Awaye Realty in Carroll Gardens, said that with each new building the avenue’s popularity had grown. “They’re hard to get started, it’s hard to sell to the first people,” he said. “But all of a sudden, once people see other people living there, it’s pop-pop-pop, like popcorn.” -NY Times profile of the "new 4th Avenue"
Actually, "other people" have been living in 4th Avenue all along.
They were there before the new towers went up. They were there until their homes were demolished to make way for the new residents.