Some of the suburbs of Boston have numerous multi-family neighborhoods (dorchester, Everett, Medford, Malden to name a few). These suburbs and others are the housing supply for boston. If someone built more housing in any of these suburbs or in east Boston it would help meet the insane demand for housing we are seeing in Boston. The Boston and greater boston area has 1000s of acres of already accessible greenery which is incredible considering the population of Boston. You can’t have the city life and also have every city have 100s of acres of parks.