I think the "calling on their shit" is mostly interpersonal stuff (like, "I'm mad you didn't make my party" and not, "you're such a hypocrite!" Something that affected their relationship, not just going off on them about anything and everything). And they seem to be pretty close if they talk like that, often even knowing each other's parents and whatnot ("shout out to Janet!"). He's more reserved if they're not as close.