I view this less as circular logic and more as a bell-curve. At the extremes, bragging and bravado likely come with limited to negative results. But identifying that there is a region of optimal show-offy-ness seems expected.

As for the market optimizing for this, i agree to an extent, but i think it might be more base than that. People in general seem attracted to this sweet spot in both business and romance. It follows that the market would similarly optimize for that.