Yes, refusing to answer some questions means it’s less general purpose than it might be, but I think people exaggerate the harm in that. Why do they expect an answer to everything?
Maybe it’s because search engines mostly don’t refuse to answer questions? But what they often do instead is show you mostly irrelevant, bottom-of-the-barrel results. But it’s more jarring when a chatbot responds with nonsense when it doesn’t have a competent reply.
Learning how to say “I don’t know” well is important for both people and machines.
Tersely refusing to answer questions that are off-topic ("Sir, this is a Wendy's") is meaningfully different than expressing unnecessary normative judgments ("Hey, you shouldn't have asked about that bad thing. You need help.") or the natural progression of them ("... and I've updated your profile so that we can better understand your troubling needs.")
The "harm" is that the power of moderation lies in the hands of the people who incidentally created this thing. They're probably doing it in good faith and the final result is reasonable, but the process of allowing creators to moderate responses of such an influential thing can be dangerous.
Not that the problem is new, see eg. Google search (it apparently doesn't refuse to answer questions, but maybe they're just silently censoring "worse" things and just presenting the "less bad" things to you), Facebook/Twitter content moderation, etc.
Maybe it’s because search engines mostly don’t refuse to answer questions? But what they often do instead is show you mostly irrelevant, bottom-of-the-barrel results. But it’s more jarring when a chatbot responds with nonsense when it doesn’t have a competent reply.
Learning how to say “I don’t know” well is important for both people and machines.