The pumpkin eater

With the combination of Anne Bancroft, Peter Finch, James Mason, Maggie Smith and Harold Pinter, why is it that this film seems to have gotten so little attention and is hardly ever shown nowadays? Pinter's screenplay for Accident, shortly afterward, had a much different reception. Could it be that audiences really discriminate that much because of color? Based upon the novel by Penelope Mortimer which was, in its turn, based upon real characters, this one really bites deep into an analysis of a relationship where power plays an eminent role.