There is no reason to believe that intelligence, in whatever form it takes, ever stops being energetically expensive. Is it possible to imagine selection pressures that would select for high intelligence over other factors? How harsh can an environment get, or how easy, before something like brute strength or rapidly breeding is always a cheaper strategy?

Some rules are universal, because they're thermodynamic. That's not to say that your species of intelligent individuals is impossible, but it is unlikely. When you really take the time to think through these scenarios, you often find that there is no justification to assume that exceptional intelligence would evolve.