To play 75% of a MLB 162 game schedule you need to play in 121 games (rounded down from 121.5).
Right now the Sox have 3 players--Duran, Story, and Rafaela--who have played in 148, 148, and 146 games. No other Sox players will get to 121.
No other AL team has just 3 players assured of playing in 75% of the games. The Jays, Yankees, Tigers, Astros, and Guardians, all have 6 or more players sure of playing in 75%. And the Mariners have 5 who, however, have played in 151, 150, 149, 148, and 130 games All 5 are very likely to play in at least 85% of the Guardians games.
Here are the names and OPS's of 6 Sox players not playing in 75% (121 games or more) of the Sox games: Devers .905, Refsnyder .863, Anthony .859, Gonzalez .821, Bregman .820, Abreu, .811, The top 3 OPS's will all finish having played in less than 50% of the Sox games this season.
I think it's pretty obvious that Cora gets the blame for the lack of good hitting on the Sox. He simply didn't play his best guys.