He has had great trades. I put him as a top 10 GM but far from the top 5.
The trades that quickly pop to mind are:
Capps for Ramos
Guzman for (was it both Treinen and Roark?)
Milone, Norris, Peacock (and AJ Cole?) for Gio
Souza for Turner and Ross
Meyer for Span
Krol, Lombardozzi, and Ray for Fister
We can call those all great. We can't really complain about what Ray became or that Treinen's best work was elsewhere. Those deals all were before the 2015 season.
There were the contenders need relief help trades:
Pivetta for Papelbon
Rivero for Melancon
Treinen and Luzardo for Doolittle and Madsen
Those were 2015-2017.
Chronoligically, next there was the "oops" and the botched breakup of the 2018 team:
Giolito, Lopez, Dunning for Eaton.
Nothing for dealing Gio, Murphy, Kintzler, and other pieces.
Then there was last year's breakup, which I think went well.
All told, I'd say he hasn't had a big hit since 2014-15 and the Souza deal. He dealt a lot of pitching since then, which eventually became needed because the studs he dealt weren't there to take on roles here. What killed them is they stopped backfilling the pitching dealt away. They tried with high draft choices, but they did not develop in time here to be useful.