Count me among those who is surprised at the reserved or negative reaction of some.
I will not rehash all of the points and will instead focus on a few.
Yes, the Sox look like locks to make the playoffs but with about 60 games left, I was not looking forward to needing to go with 3 bona fide starters and then trying to stitch it together with Johnson, Pomeranz and others from the system for the last two spots. There's still a lot of season to be played.
Johnson might be serviceable but he is still unproven and has never given them much length. Pomeranz has looked awful all season, including in AAA. Even if both could keep them in games enough such that the offense could bail them out, the effect that the resulting heavy usage might have on the pen would be felt in October, if not before. And we're talking about a pen that itself needs some help, arguably.
Another factor is the importance of avoiding the one game playoff. Eovoldi is not a cure all. But I think he increases the odds of getting more quality starts out of the 4 spot and winning the division. Sacrificing Beeks for that doesn't bother me.
And let's not forget that Eovoldi might prove important as a starter and reliever in the playoffs. Who else is the 4/reliever from the starting staff? E-Rod could come back in about three weeks (at best probably) but has been injury prone throughout his career in Boston, Pom has been hideous and Wright is coming back from a knee injury and has felt soreness in that same knee. One look at Dustin Pedroia's 2018 is enough to dampen anyone's hopes around Wright this season (not that any two players are identical).
Last, I come from the school that when you have the chance to win it all, you take some chances on the way to shoring up the holes on your team. I know I am in the substantial minority, but I can't really fault Lou Gorman for the Andersen-Bagwell deal. Yeah, it should have been just about anyone but Bagwell, but the idea of trading a prospect for a vital bullpen piece (or starter) made sense to me at the time in that case and makes sense to me now.