As a newcomer to the community, I'm ill-equipped to comment on norms (and am also commenting on something nearly five years old) but my intuition agrees with your assessment of how we view those with whom we disagree. With that said, it doesn't seem to fully cover the relevant scenarios, though. Take, for example, a request for clarification or explanation of some jargon; one can make such requests kindly or non-kindly (no effort to be kind) or unkindly (antagonistically or degradingly). In such a case, if behooves the requester to be nice, because that is more likely to yield a beneficial response, but one could still consider the relevant meaning of "nice" unresolved.

To continue the example, I value an indication that the other person has considered the value of my time before asking me to clarify something more than I value the actual politeness of the form of the request. Suppose I'm interacting with another newcomer to the (unrelated-to-LW) community; I consider "I can't find a relevant definition of \"fully unlocked\" on Google" nicer than "can you please tell me what \"fully unlocked\" means?" when operating in a context where I know that the community's definition of the term is well established because the first person has indicated an acknowledgement that the time of others is valuable by attempting to find the answer themselves before answering. It looks less nice, but that's mostly because it's structured less politely. Neither is sufficiently unkind that I wouldn't answer, but the former would get a "thanks for searching; I'll try to post that somewhere more prominent" or similar in addition to a link to the relevant definition, whereas I would need to remind myself (for the reasons given here) of the need to be nice to the second poster instead of just posting a direct link (or worse, a LMGTFY link).