Interestingly, most sites do, even though he wasn't with the team. I guess because he was technically the manager.
The Sox record under Farrell that year was 50-64, but he did so with Bradley not hitting like the monster he was under Lovullo. Not sure if Lovullo's impact on Brdley is actually quantifiable.
Of course, the entire point was that Farrell - and only Farrell - is credited with a last place finish, which I think is an oversimplification of that team. I don't think he's much of a manager, but I do think he isn't going anywhere soon and he's better than many Sox fans give him credit for. and as we have learned in the past, it's usually easier to get a worse manager than a better one. For some reason, there were fans calling for Francona's head every year. I'd think his replacement should have taught us all a lesson about being careful what you wish for.
Really, since we all watch more Sox games than any other team, it is easier to spot Farrell's mistakes and his total becomes much larger. But there are plenty of worse managers out there holding MLB jobs...