No, such stories are not limited to any one ideology. But each ideology has certain institutional and ideological blinders that helps it happen. The last two examples are particularly instructive. Taibbi and Kriss got away with their behavior for as long as they did because they had a reputation of fighting viciously for the cause, particularly when it required someone who was willing to rejecting normal standards of respectability and civility.
What made them so many fans was precisely their viciousness, their willingness to berate and insult, because surely their political enemies are such horribly evil people that they don’t deserve the protection of civilized norms. Kriss was even part of a movement called the Dirtbag Left: “a term coined…to refer to a style of left-wing politics that eschews civility-for-its-own-sake in favor of subversive, populist vulgarity.”
In other words, these writers were lionized and promoted precisely because of the characteristics that marked them out as predators. It’s hardly a new phenomenon and has even been immortalized on film. These guys are all the hippie boyfriend in “Forrest Gump,” who can’t help smacking around his girlfriend because “it’s just this war, and that lying SOB Johnson.”