I think you are misreading the GP, they said "A deep-thinking LLM aided me through research *with fact-checking, agents, tools and lots of input from me*", which I read as implying they did the fact checking, and not the LLM.

They can cite their sources which can be double checked by the user and verified. I guess at that point the user would just tell you what they found and use the same sources and people would be way less hostile than they currently are.

Whether the hatred is justified or not, the openness of said hostility just breeds users who'll hide their usage and deliver the same content, just repackaged enough in attempt to throw off the BS smell. And now you, the user, might be two paragraphs into something that may be truthful enough to fool you unless you're also an expert on the topic. I'd rather know up front what their source was and weigh the data with that in mind.

Otherwise we're now all going to have to assume everything we read is AI generated and suspect everyone else is going to look at our own content under such a microscope. Maybe that's a positive though.