I agree with the general shape of your argument, including that Cotra and Carlsmith are likely to overestimate the compute of the human brain, and that frontier algorithms are not as efficient as algorithms could be.
My best guess is that a frontier model of the approximate expected capability of GPT-5 or GPT-6 (equivalently Claude 4 or 5, or similar advances in Gemini) will be sufficient for the automation of algorithmic exploration to an extent that the necessary algorithmic breakthroughs will be made.
But I disagree that it will happen this quickly. :)
I agree with the general shape of your argument, including that Cotra and Carlsmith are likely to overestimate the compute of the human brain, and that frontier algorithms are not as efficient as algorithms could be.
But I disagree that it will happen this quickly. :)