Max, I know your main issue with the narrative regarding bullpens is with the designation "closer" and what constitutes "saves" and "blown saves." But I cringe every time you bring up the Sox' '21 postseason... because basically every Boston reliever failed at least once. Every game was a stressfest, even when they won:
Whitlock gave up a bomb to Stanton; Barnes loaded the bases in one IP vs. Tampa and wasn't used again; Robles blew a 2-run lead via HR, 2B, 2B in one IP; Houck gave up a HR to Franco; Braiser blew a 2-run lead via 2B, 2B, 1B in one IP; Houck blew 2-run lead on Altuve's 2-run HR; Robles allowed a game-losing HR to Correa; Sawamura: BB, 1B, HBP, SF in one IP; Darwinzon: 2 HRs in one IP; Whitlock blew the lead on an Altuve HR in the 8th of ALCS Gm 4... and Boston never led again; then Braiser, Robles, Taylor, Houck, and Ottavino each gave up a run or more in the last two games.
The bullpen was so bad that Cora had to use Eovaldi and Perez in back-end duty, and both starters also got lit up. Pivetta was a hero, but even he lucked out when Renfroe kicked Kiermaier's drive into the... yup, you know where.
Bottom line is that the Red Sox relief crew was not good enough to take them to the World Series, unlike Houston's, which added better arms at the deadline.