Worth remembering that Kerr and Simon gave mixed to negative reviews to the three earlier Sondheim-Prince shows of the 1970s. They both liked Night Music best, but even though Kerr gave Night Music an ultimately favorable review (it might be termed mixed leaning favorable), he expressed enough reservations that I doubt his review helped the show at all. Mildly favorable. Very mildly favorable.
The only reason Pacific Overtures played as long as it did was because Hal Prince bailed it out almost every week of its run. If memory serves, it lost money all but two weeks of its run. Prince said that he spent half the money he had saved over his career to keep Pacific Overtures running.