I am 100% sure that in this age of "marginal gains", the pro tour teams would not go for anything that doesn't give them it unless severely hamstrung by sponsorship deals. And I doubt that the wheel sponsors don't have multiple sizes available.
And I think you're severely overestimating wheel life span for modern models, at least due to the fact that carbon is more brittle than more pedestrian materials. Just look for Pogacar's fall earlier last week in the Giro to see how a simple flat tire makes the whole wheel a risk.