Long time ago, me and a friend of mine had a joke about PMs: to calculate how managers combine, you multiply their performance rates: two poor managers (e.g. 0.5*0.7) will give you worse performance than if you had one bad manager. My similar formula about AI and developers is that it works like raising to the power of two: if you have a bad dev, you get 0.5^2: more mess more quickly. If you have a great dev, you get 1.5^2 - exponentially better :)
I've used an even less-kind framing in the past: incompetence is multiplicative. Two half-wits together gets you a quarter-wit.
I had a similar thought earlier this year - competence is additive, incompetence is multiplicative.
... quadratically better
Maybe he had AI assist him with that comment