It isn't a baseless witch hunt if the witches are real.
Creating a social stigma against the use of LLMs is constructive and necessary. It's no different than HN tone policing humor, because allowing humor would turn HN into Reddit.
How is randomly branding people without knowing "constructive and necessary?" Seems like it is completely self-defeating; you're going to make the accusations meaningless because if everything is "LLM" then nothing is.
I get the point you're trying to make, but it's worth pointing out that the entire point is that it's not people getting branded but nebulous online entities that may or may not be people. It's a valid criticism that the accuracy of these claims is not measurable, but I think it's equally true that we no longer are in a world where we can be be sure that no content like this is from an LLM either. It's not at all obvious to me that the assumption that everything is from a human is more accurate than the aggregate set of claims of LLMs, so describing it as "branding people" seems like it's jumping to co me conclusions in the same way.
Things should be judged for their quality, and comments should try to contribute positively to the discussion.
"I suspect they're a witch" isn't constructive nor makes HN a better place.