I had actually started a thread breaking down each trade he had made since taking over but lost it.
Objectively speaking, he has acquired 7 of their top 30 Soxprospects via trade and several other from 31 to 60 who most likely won't make a difference. De La Rosa may be an exception, but who knows? They needed depth as part of the soft rebuild and they have gotten it. Even if one of them hits, it's a success because they aren't throwing away a couple mill at washed up guys like Marwin Gonzalez and maybe getting marginal improvements for less money.
For a team that I think will spend to the cap when the time is right, that stuff adds up. Some of you will disagree, but John Henry has always shown a willingness to spend when things are looking good, and right now, they don't have the comparable talent (thanks in a major way to an extreme whiff with Chris Sale) as at least three of the other teams. If he missed his window by not pouncing earlier, then I think it's fair to be more critical, but I am on board with his approach and will reserve judgement through next off season.
The ones most open to questioning from my point of view are the cost controlled players like Benintendi and Hunter Renfroe. Could they have used Benny this season? Sure. Would he have been a difference maker in making the playoffs? I don't believe so, but YMMV. I think Binelas having a chance at being a minimum salary bench guy with potential for more is a good get. They don't acquire him without taking on JBJ.
Wincowski may not be the most exciting guy out there, but if he's their more effective and cheaper Matt Andriese guy next season, or maybe he's a 3rd or 4th piece for a small market team then I consider that a win.
@nvalvo has it right though - getting Whitlock and signing him to a ridiculously team friendly deal and then developing John Schreiber into a dominant reliever for absolutely nothing is how you win without rolling the dice on free agent relievers. Signing Miguel Bleis is another potential difference maker.
TL/DR I think the majority of his trades have been inconsequential, with one huge win, a loss (Springs) and some pushes depending on what your expectations were with Betts and Benintendi's returns. I think Bloom has made a lot of non-flashy but incremental improvements getting under the cap without truly taking a risk.
And FWIW, Springs has struggled over his past 4 starts, giving up 11 ER in his last 18 innings.