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Obviously, they're not voting. Or, if they are, we've already accepted that automated voting is acceptable. Are they just out trolling too, to get votes?

I think they are trying to get upvotes from authors or curation services like @topcomment

Or are they representing their own stand-alone vote-harvesting system, of the kind we've seen automated before? Color me curious.

Are these AI-generated comments of a higher quality than the usual stuff that you get from human beings doing a drive-by?

They are higher quality than the 'nice post' comments, but I don't think they are more valuable for the author of the blog.

So, no worse, and just equal, all things considered. I think that's what we have to go with, assessment-wise.