Depends on what you are calling taller
going from a 235-70-16 (29 in.tall) to a say 265-75-16 ( 32 inch tall) will cause a drop in mileage and power. Most try and stay around a 245-75-16 ( 30.5) for some extra height but not so much power or mileage drop.
You will get a ton of different answers to the queation and it all goes to what works for that person, where they live, where they drive and how they use their vehicle.
For instance I like the way mine runs with the 265-70s ( 30.7) up here in the flatlands of Ohio, but when I go down home to the hills I wish I had 4.10s in ( as long as they don't rust away in the garage) or shorter tires