Because the "rate of improvement" is only astonishing in well understood areas and really only astonishing if you yourself are not that great at what you do.
This is a bold vague claim many on HN make, but never put back-of-napkin numbers on. e.g. do you think agentic Opus 4.7/GPT 5.5 are 95th percentile coders but you're 98th percentile? Or are you saying you're a middle-of-the-road 60th percentile coder and AI is 20th percentile so only 20% worst programmers should worry? Let's be specific about the claim being made.