Wikipedia
Your partner's experience is entirely standard with attempting to correct Wikipedia about something in which they're an expert. It happens eventually to every academic who tries to interact with them.
When it happened to me, I looked at the profiles of the people who were laying in to me and found that they basically have PhDs in watching television: they had no relevant general qualification and certainly none in the particular topic.
I do still look stuff up on Wikipedia. It's good for subject that consist of a list of unconnected factlets, such as a city (history, amenities, transport, sport, etc).
But for something like a concept in mathematics, where one wants to scrap, re-write and control a whole page, trying to correct it can only lead to conflict.