Sanctimonious
Attitude? No. But the desire and  ability to do research and fact check perhaps. It is so easy to find reliable fact checking sites, but instead, name calling and other childish threats are used with zero facts or thought which immediately cause me to disregard them entirely. Just because some carnival barker says it is the best show in town, don't believe it until you see it. Erosion is the decline of research and fact checking, not about the right versus left.