While I have no doubts that they could build NN capable of recognizing GPT-3 text I believe that this would still pose a problem given the amount of content to be analyzed at the scale that Google deals with
I'm sure Google out of all entities could handle scale.
That said, there might be a different threat to Google. GPT-3 seems really useful as a search engine of sorts (with the first answer implementing the 'I'm Feeling Lucky' button). Tune it for a query syntax, and for getting the 'top X' results somehow, then we just need the web corpus and a basic filter over the results. We could have a very interesting Google competitor.
That said, there might be a different threat to Google. GPT-3 seems really useful as a search engine of sorts (with the first answer implementing the 'I'm Feeling Lucky' button). Tune it for a query syntax, and for getting the 'top X' results somehow, then we just need the web corpus and a basic filter over the results. We could have a very interesting Google competitor.