I think people here having been underrating the importance of Martin Perez and how he may be the key to the season.
IF the Big Three can rebound to win, say, an average of 10 games apiece -- those 30 total wins in '20 (2x their 15 total wins in '19)... is a plus-15 from a year ago, which can account for Porcello's missing 14. And the Sox' record would still be plus-1. Or 85 wins.
Meanwhile, IF Erod regresses but still stays good -- let's say 15 wins -- now we're at minus-3. Or 82 wins.
So to get back to the 90-win column, which is usually Wild Card contention, all Boston would need is 8 measly wins from Martin Perez.
(this is assuming the same production from the up-and-down bullpen -- and though it may be optimistic to count on all three of Sale, Price and Eovaldi to bounce back... their 30 Ws can be distributed in any number of feasible combos... like if just one can re-discover the touch and win 15, another 10, another 5, etc).
But clearly, it's all on the Filler P's.