Well, not all Cayman's, but, I think, for example, the GTS models could equal the horsepower of the Base Carrera and be priced so that instead of the Cayman being ~$2K more than the Boxster it was ~$2K less and the horsepower on the Cayman/Boxster would be equal to each other as well.
Porsche's "message" is that it's not all about horsepower, but that driving dynamics are just as or even more important than raw power. Yet, the horsepower games they play with the Cayman S, and now the GTS, to insure that it's "appropriately" less powerful than the Base Carrera undermine that message. If it's not all about horsepower, why does it matter that the Cayman/Boxster GTS has the same, or even a little more horsepower, than a Base Carrera? The Carrera is a different car with different dynamics, so you can't really compare them based just on horsepower; the Macan S has more horsepower than the Base Cayenne but does that make it better, or is it just different?
Obviously, they can't make this marketing change right now with the current models, but, in the next generation, if the Cayman/Boxster switch to 4-cylinder turbo engines, they could, assuming that the Base Carrera doesn't continue to have the same engine as the Cayman/Boxster S models. Although, they still have the problem of repricing the Cayman under the Boxster after all these years of claiming it isn't just a Boxster Coupe.