I would probably consider changing "power" to "size".
My 2016 Subaru BRZ had 200 horsepower, averaged 32 mpg, and was $26K. Not a bad combo, if you ask me. A decent amount of get-up-and-go when you want it, but decent fuel economy when you don't. But it was also just a small 2-door sports car. Tiny trunk and worthless rear seats.
I think they mean economy as in cost (money). You can make a powerful inexpensive engine but it will have a worse emissions profile, or a powerful expensive engine that has a better emissions profile. But you don't get a powerful, inexpensive engine that also has a good emissions profile.
My 2016 Subaru BRZ had 200 horsepower, averaged 32 mpg, and was $26K. Not a bad combo, if you ask me. A decent amount of get-up-and-go when you want it, but decent fuel economy when you don't. But it was also just a small 2-door sports car. Tiny trunk and worthless rear seats.