First, literally 100% of the blog posts, reddit replies, recipe books, and so on, will always list botulism as a potential danger of canning just about anything, but especially the common "garlic infused oil" (just do a Google search). It's unlikely that the model decided to trim/ignore this dangerous caveat (again, found in basically every corpus mentioning garlic infused oil). Maybe the LLM would've mangled the (very important) step of roasting the garlic to dehydrate it, but I very much doubt the health disclaimer would've been omitted.
Second, note that there's no actual conversation link, just a screenshot, adding to my skepticism. Is the screenshot doctored? Who knows. Sure got a lot of attention.
Third, in my experience, LLMs tend to be overly cautious, and not the opposite. I remember a few months ago where getting ChatGPT to teach you "unsafe rust" had a disclaimer if you told the language model you were under 18. Maybe if it was something more obscure, I'd believe the poster, but botulism and long-term storage/canning go hand-in-hand. Like raw eggs and salmonella[1].