This kind of dynamic must account for all of the times that I've seen people on HN write that they are "genuinely curious" about something: otherwise people might think that their questions are rhetorical and intended to be unanswerable or make fun of the other party.

Although rhetorical questions do exist, including questions used as arguments or to belittle, is it bad that this interpretation of questions has become so common that people have felt the need to disclaim it somewhat routinely?

I'm genuinely curious. :-)

On the one hand, one should aim to communicate successfully. If people routinely misinterpret questions, then one might want to stop using questions and stick to statements.

On the other hand, such misinterpretation - even though it's probably often an honest mistake - is also a signal that the other person might have incompatible goals for the conversation. I try to follow the Principle of Charity (https://en.wikipedia.org/wiki/Principle_of_charity), the conversational equivalent of "Be liberal in what you accept". But if the other person doesn't do the same, the conversation can become unproductive, and I just disengage.

In addition to charitably reading the words of others, I do want my words to also be charitably read. Not (just) because it's hard not to leave room for misinterpretation, but also because it just feels better. After all, I joined the forum for fun.