My friend shared some screenshots of ChatGPT giving a convincing response to the prompt

    > Outline a proof of the snake lemma

Satisfied with the output, my friend then asked it to outline a proof of the Riemann hypothesis, and rather than being tricked into gibberish maths jargon or miraculously producing such a proof, ChatGPT accurately and briefly summarized the hypothesis, explained some limitations of current knowledge and paths such a proof might take. It did a better job at it than I would have.

Because of these examples, even though they are examples of mathematics rather than computation, I don't think it's fair to be so dismissive. It's a bit of a well known fun fact that a lot of professional mathematicians are terrible at mental arithmetic.