I don’t think GPT is any better. I swear GPT-3 was the golden area of LLM prose. With a good fine tuning, you really couldn’t tell that an AI was writing (except for when it would devolve into utter nonsense lol)
Often I'll tell it to summarize what it said only because it's providing too much detail, not that it's using esoteric language or weird claudisms.
No idea why people are still using Claude models.
My impression is they started on Claude Code and never tried Codex or other harness+model combos