Building housing for the rich has a displacing effect. Either they are locals and their old place goes to sale or rent or they no longer displace existing residents. And absent sweetheart deals incoming rich with their increased tax revenues should allow the city to upgrade public transit, build public housing or other solutions. But it is up to the city to solve their problems.

Apparently in Boston contrary to concerns luxury high rises didn't act as gentrification locuses but stemmed its tide in other areas instead.