They might have been ignoring robots.txt all together so it didn't even occur to them that's a thing.
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The irony of a leading AI company not having a proper robots.txt file is too good.
Did OpenAI just accidentally leak the next big ChatGPT upgrade?
An OpenAI blogpost may have accidentally leaked details about a faster, more accurate GPT-4.5 Turbo model with a larger knowledge base.
androidauthority.com