FiDi's residential population is about 60k now, which is triple what it was in the early 2000s (and probably around double what it was around OWS). Notably the US census includes Battery Park City in FiDi, which significantly skews the numbers versus the business streets (where the protest was).

By contrast, most of the residential neighborhoods in Manhattan easily clear 100k people, and are not as segregated in terms of business and residential streets.