bad code should be called out. It's reasonable to feel frustrated by bad to terrible decisions that your predecessors made and left you to clean up the consequences of.

when a group of people is presented with a shitty situation verbally commiserating with your co-sufferers is a form of group therapy. Yes, it has to be tempered with hope and humor, but... bitching is good. Cynicism actually helps ward off burnout (barely, but it's one thing that contributes to warding it off).