I’m not sure the same happened with “delve.” I saw an analysis of paper abstracts showing a clear uptick of “delve” starting with the mass-adoption of ChatGPT. Maybe it suddenly became a trendy word — especially in paper abstracts — or maybe more paper abstracts were edited by ChatGPT.
Combining the various "tells" of an LLM (em dashes, delve, grammatical signs etc) with the context (Reddit comments vs professional setting), you could establish a rough probability it was AI generated. At this point, it's the best we can hope for.
same thing happened with “delve” — these are just words and grammar, people use them
there is no accurate way to tell whether text came out of a neural network or not