Balance is sometimes overrated because most of the expectation about how to be a great professional comes from overzealous 9 to 5 mediocre professionals. That doesn't mean life is about burning out and crashing against a wall of mind wrecks every few years of course, but for many people it's possible to keep let's say a 85% work 15% hobbies, relaxation and workout and society needs those guys at their maximum capacities.