I think it's a cool perspective, but the not-so-hidden assumption is that for any given domain, the efficiency asymptote peaks well above the alternative.
And that really is the entire question at this point: Which domains will AI win in by a sufficient margin to be worth it?
> the not-so-hidden assumption is that for any given domain, the efficiency asymptote peaks well above the alternative
This is an assumption for the best-case scenario, but I think you could also just take the marginal case. Steady progress builds until you get past the state of the art system, and then the switch becomes easy to justify.