This is true, but the problem has become more concentrated with the advent of RNAV. Depending on wind direction and which runway Logan was operating, I had flights departing directly over my place in both JP and later Somerville every 60-90 seconds. The precision with which they do this is incredible, and also kind of annoying.
Spreading out the traffic would do wonders. Having witnessed this firsthand, it's not super surprising that complaints are concentrated when the noise is too.