1. The team traded a Top 10 player and got no All-Star ceiling out of it. So from a baseball perspective it was a bad trade. Knowing in 2022 that the San Diego Padres traded multiple Top 100 prospects to the Nationals for Juan Soto makes this harder to swallow, even with the extra control that Soto has.
2. That said, if you rejigger the notion of the trade to "The David Price salary dump featuring Mookie Betts", then the baseball trade at the time was okay. Jeter Downs was seen as a high floor prospect (whoopsie) and Verdugo was arguably the Sox' best player in that forsaken 2020 miniseason.
3. Honestly, the big problems the Sox have been more before the FA picture loomed. They and Betts and Bogaerts never got close on extensions. When Betts only had one year of control left, it did take away some of Boston's leverage. From what was reported, there were not a ton of buyers, though again we don't know exactly what ownership was looking for and whatnot. Were there more teams in the position of - say, Minnesota (101-61 in 2019) who might have been willing to trade for Betts knowing they were only getting the 1-year? I don't know.
4. The real Monday Morning Quarterback play is to wonder whether Boston should have dealt Betts at the 2019 trade deadline. I totally get why they didn't and largely support it - there was a wildcard chase after all. However, if the Red Sox really knew the state of play contractually, looked at the jumble of teams they had to fight off to get a wild card spot, and the alarming state of their 2019 pitchihg staff ... it would have taken stones, but that would have been the time to get the sort of bidding war that would have gotten some All-Star sort of ceiling.
While I think there were plenty of extenuating circumstances, the top level story of the Betts trade is what it is - and fans have every right to be bummed out about it. The team simply did not get the organizational jolt you'd expect by dealing a player of that caliber.