I've noticed a considerable drop-off in HN commenters who are unable to deal with the substance of a comment if it contains errors in spelling or grammar, so I don't think this is the issue it used to be.

It's still daunting posting in a second language, and LLMs are an attractive solution to that (depending on your definition of 'solution').

Is that an actual drop-off in commenters, or in comments? The latter is readily explainable by “commenters who would previously call out the errors now choose to not engage with those comments/posts at all”.

In any case, I don't think it's a bad thing to want to communicate as clearly as possible, and if an LLM helps you do that, I ain't one to judge. Sure, ideally I'd want to read folks' thoughts without the LLM-induced layer of vaseline smoothing them over, but even that's better than not reading them at all :)