Griffin did cross a line, and much of the left is saying so too. Even the New York Daily News condemned Griffin on its front page.
Griffin, though, is a fairly mainstream figure; the left may well believe this could be a bridge too far - proof that the "resistance" borders on fanatic, irrational hatred.
As for Barron, when I was eleven years old I read The Conscience of a Conservative. Why wouldn't Barron be reading the news about his dad, the good and the bad? But this? Hell, when I read the story about Griffin's photo, I didn't want to click on it. Griffin posing like Jihadi John? Hell, that the sickest of the sick.
Let Kathy Griffin get painted as the face of today's left. Or let her light send the roaches back scurrying under the fridge.