Considering he's their best pitcher, he was pitching an absolute gem, he had only thrown 70 pitches and he averaged 100 pitches per start in the regular season, he hadn't given up anything hit hard, and hadn't lost any of his velocity it was a brutal decision and most likely lost them the World Series.
It wasn't long ago when managers rode their stud starting pitchers in the biggest games and often times they were rewarded with World Series rings because of it. This is right there with the Blake Snell decision and some others we've seen. It's something which has made the game worse IMO and it deserves to backfire like it so often does.