Would Ben have traded those prospects? I doubt he would have traded Espinoza for Pomeranz. That deal is a net positive for the Sox.
Would he have made the Kimbrel trade? Probably not. So who is the closer? Kimbrel has been outstanding since day 1. Ben got a half year out of Uehara, but didn't have a good closer otherwise.
Would he have traded for Sale? Maybe? I think it would be more likely that he'd pick up more FA duds like Hanley and Panda tho. Yes, Hanley is good this year, but that doesn't erase the high price tag and lack of production the previous 3 years.
I think Theo was the best GM. He was able to keep the team competitive AND develop a farm.