John Henry is the greatest owner in the history of the Boston Red Sox. He should sell the team.  This would have been impossible to imagine in 2018, or ‘13, or ‘07, or ‘04, but every day he continues to hold an office on Jersey Street, he tarnishes those four World Series trophies. Saturday’s Boston Massacre—the team fired manager Alex Cora and five of his coaches—is just the latest instance of someone else paying for Henry’s mistakes.  As with the rest of the recent failures, Henry is unlikely to take responsibility for them—or questions about them. He has not addressed the media since 2020. A 10–17 start to the season, No. 27 in baseball, deserved some action. This one, taken hours after the Red Sox beat the Orioles 17–1, bordered on comical. Half the replacement coaching staff woke up Saturday morning in the minor leagues.…