One more time. The Sox had a surprisingly excellent postseason last year, beating the Yankees in the wild card, taking 3 of 4 from the Rays in the ALDS, and winning 2 of 6 vs. the Astros in the ALCS. They were 6 and 5 in the postseason and had zero saves in the 6 wins. They had one blown save in the 5 losses, but it occurred in the 6th inning, long before a closer would have been used.
Or how about the great Kimbrel, whose ERA in the magnificent 2018 postseason was a nasty 5.91? He still got 6 freaking saves thanks to others on that team like Kelly (ERA .79 while pitching more innings than Kimbrel), Eovaldi with that incredible relief effort vs. the Dodgers, Barnes (ERA 1.04), and Brasier (ERA 1.04).
You could of course fire back with the amazing postseason Uehara had (7 saves, ERA 0.66) in 2013, but then I would remind you he pitched just 13.2 innings. The rest of the staff pitched 128.2 innings, and the overall team ERA in the 2013 postseason was 2.59. Good as Uehara was--and he was fantastic--he needed plenty of help for the Sox to win that title. Jon Lester threw 34.2 innings with an ERA of 1.56, and Lackey 26 innings, ERA 2.77. Also: Workman, 8.2 innings, ERA 0.0; Tazawa, 7.1 innings, ERA 1.23; Breslow, 7.1 innings, ERA 2.45; Doubront, 7 innings, ERA 1.29.
This season to date the Sox have 12 blown saves, most in MLB and are now 23-27. Thus the uproar over a closer. However, the Rays are 28-21 and have 10 blown saves, the Padres 30-19 with 9 blown saves, the Twins 30-21 with 8 blown saves, the Jays 28-20 with 10 blown saves, and the Mets 34-17 with 9 blown saves. So, me, I'm having a little trouble blaming this entire freaking season on not having a great/good closer.
As moonslav has pointed out, this is not a strong bullpen, which is far more important than a good closer. And let's not forget our incredibly inconsistent hitting, so-so defense which gives up crucial unearned runs, etc.