I've never seen the word "delve" show up with such frequency in the pre-AI era, but now it's an overwhelmingly large signal of LLM-generated text, so I'm not sure where that came from. Ditto for vomiting emojis everywhere.
https://books.google.com/ngrams/graph?content=delve&year_sta...
Mirroring real human text is only the basis of training. Afterwards they get aligned a.k.a. lobotomized.