True, I agree. It's a good thing to accept a language's limitations and areas of suitability, without any judgement about whether the language is good for all purposes - which is likely not a good goal for a language to have anyway. I like that example of Roc, how it's explicitly planned to be not self-hosting. It makes sense to use different languages to suit the context, as all tools have particular strengths and weaknesses.

Off topic but I wonder if this applies to human languages, whether some are more suited for particular purposes - like German to express rigorous scientific thinking with compound words created just-in-time; Spanish for romantic lyrical situations; or Chinese for dense ideographs. People say languages can expand or limit not only what you can express but what you can think. That's certainly true of programming languages.