This has nothing to do with LLMs. If incorrect info can get onto a reputable resource, that info will seem authoritative, and it will be incorrect - that's not surprising. LLM's use publicly available info in their training, and often times publicly-available info is incorrect. I feel this is just as interesting as the base claim of 'I can get incorrect info onto wiki pages', no more interesting, and no less.

If somebody is trying to put out incorrect information on the internet, and they choose a small enough niche, it is not at all surprising that they can succeed.