I'm gonna say Eriksson.
I feel like the flak he gets over his contract far outweighs his actual contributions or lack of contributions on the ice.
To hear some talk, he never does anything and is a completely useless anchor of a player. But then you look at his actual stats and deployment, and even if he's not the offensive player we were hoping for his 200 ft game and defensive play are very good. He's a responsible winger you can literally put on any line, and every now and then he shows a bit of his old magic and produces, sometimes like against Florida multiple times in a night.
As for the others...
Pouliot/Schaller/MDZ/Granlund get all the criticism their play deserves.
Whereas, Goldobin and Gudbranson simply aren't producing to the level they need to be, and especially for Guddy have been defensive liabilities.
There isn't anything particularly unfair in the general criticism of Gudbranson, even if it gets hyperbolic. Goldy's lack of production apart from Pettersson and in the later half of the season so far combined with his struggling to keep up with his defensive responsibilities also make criticism of his play fair. Hopefully Goldy can figure it out as a young player, Guddy likely needs a new team.
To me, whipping boy means mostly undeserved, or overblown criticism that happens regardless of what they do... so yeah Gudbranson deserves his Criticism, so Loui Eriksson is my selection.