I have a hard time blaming Papelbon for the culmination of a whole month's epic failure in 2011 that took a team effort to achieve, we should have never been in that position to begin with and it's a laughable concept to suggest we would have gotten very far in that postseason to begin with with the state of the team at the time. His blown save was the nail in the coffin, but it wasn't the reason we didn't advance into the playoffs in 2011, not by a longshot. Daniel Bard and the rotation both had far more to do with what went wrong that year.
As for 2009, that was literally the first time he ever got beaten in a critical moment,
I'm fine with that track record personally, the greatest closer that ever lived had more and more heartbreaking letdown moments for his team than Papelbon ever could have had, and that doesn't take away from his legacy one little bit. let's start with the world series Mo literally blew in 2001 and the ALCS he sure helped blow in 2004, do those moments far far far worse than anything Papelbon did to hurt us, take away from his overall excellence? No. And the same to a lesser extent applies to Papelbon's few failures.