As a manager, I absolutely would hire someone smarter than I am. I don’t understand those who would not. Admittedly, those people are rare on the ground.
In raw mental horsepower, my intern from some years ago was smarter than I am by a bit. Stratospheric IQ and driven too. She was not as well-read or as knowledgeable, but definitely had a bit bigger engine. I’d hire her for just about anything without question. She is the only person I’ve ever been able to give complex tasks to and she could just do them. I miss that every day.
Hiring people smarter than you are is how you avoid an organizational bozo explosion.