You can reasonably ask an unreasonable request. If the neighbour politely told me that they don’t like me walking past their house on the public sidewalk, I will ignore such a request because I’m entitled to walk on public property. Just like how I believe it’s unreasonable to request people do not link to public web pages.

A reasonable request would be “I never published this publicly or have since deleted it, please stop reposting it”

The subjective part is they believe it is reasonable to request this while others do not.