One has no hesitation in correcting somebody whose age (a child), or station (such as a student), or lack of pretence to expertise render them entirely dependent on more learned interlocutors for sound knowledge. I can argue with somebody about Javanese astrology, but since I am perfectly ignorant on the topic, I have to concede that a Javanese stargazer has the prerogative to gainsay whatever nonsense I speak. That isn’t impolite or presumptuous (done gently); it simply takes account my situation relative to another’s.
In circumstances where relative status remains undefined or unclarified, speakers frequently fall into presumption and condescension on the premise that if one’s interlocutor were an intellectual equal, one would already know them, or would be able to tell right away. So, prodigies and post-graduate students, and (inexcusably) women and people of colour, often suffer patronising airs from speakers who don’t already register them as interlocutors worthy of respect. We can explain this phenomenon readily enough, though with censure (whether explicit or tacit) to the condescendor for not anticipating that they too rapidly and inaccurately guessing at the status of the interlocutor.
Often enough, two parties with roughly equal claim to expertise speak to one another, each as if the other were a child or a student. The two are known to one another; each is aware that the other is a scholar of standing. Still, one will treat the other as if an ignoramus, a bumpkin, a clod. How do we explain this with even a modicum of charity?
Or the other way around: If I know and respect you, why would I try to change your mind on a topic of mutual interest? ‘Why’, or how? If I simply set out my reasoning, explain how my position is joined-up relative to other notions we (presumably) share, and account for its benefits — what more can I do?