How is Costa's run now more difficult to read? (I the hotel arc was awful. But, everything pre-"Cobra Civil War" was good. (It was the only Joe worth reading at the time.)
There are differences between Sitterson and Dixon, the most important being that Sitterson has a bigger mouth.
Dixon is conservative (and has made some questionable choices about where he works). But, he is not obnoxious about his political leanings. And, until recently, Dixon's conservatism has never veered too far from the American zeitgeist. (One could argue that today. But, that is another set of questions.)
Sitterson may be a lefty. (I really do not know.) But, it was not his politics that got him in trouble. It was his mouth. Sitterson took a unifying global event (a massive terrorist attack that killed ~3,000 people) and made it about himself in the most obnoxious way possible. He downplayed the significance of the event and its impact on every aspect of American life.... And, he did this while working on a property with a fan-base that tends to skew right and (more importantly) will vote with their dollars. He deserved to be fired, if only for being stupid.