Do you know of any other examples of such blatant lies being pushed by search engines with their AI summaries?

Not specificially but I'm glad you asked. Google's Trusted News Initiative and youtube's Authoratitive News Initiative trace back to late 2017 / early 2018 and can be seen as the first foundational example of global online digital information "authoratitiveness" being addressed as an issue for all internet users worldwide.

I've been subscribed to their newsletters & whatnot for about as long as it's been around yet it still shocks me to see how easily something that's a real and tangible threat to child safety online (e.g. Elsagate) was used as an excuse to create a global apparatus to push sanitized, sanctioned and sterilized versions of "consensus."

https://journaliststudio.google.com/

https://newsinitiative.withgoogle.com/resources/trainings/verification/