Compared with “Us,” also in theaters now, the movie feels benign, almost polite — which can’t possibly be what Lipsky had in mind. No, he seems determined to shock, but his films are like those proverbial trees, falling noisily in empty forests. That’s not to say Lipsky should stop making movies — one hopes The Last won’t be his last — but that it might be a good time to take a serious look at what he’s trying to achieve, if hardly anyone’s paying attention.