"Uncanny valley" is actually the opposite of what you mentioned.

The uncanny valley hypothesis predicts that an entity appearing almost human will risk eliciting cold, eerie feelings in viewers. For CGI and things that have visual queues, the minute differences in movement and facial muscle contractions contribute tremendously to our emotional responses to the "realness" of the thing.

ChatGPT has no such thing as it's virtually impossible to differentiate between an AI bot's writing and a human being's writing. It simply typically reads as concise and grammatically correct, if generic, university educated writing.

I actually WISH that there was a "tell" that allowed for an "uncanny valley" like experience, but chatGPT is as close to real as "real" is.