There are instances many leaders who succeeded in life without formal education, but the modern life changes make different criteria for leadership role.
In my opinion, education must be a part of it, it does not have to be a formal one, we have seen some opinions that the world is the largest and biggest classroom ever, so it is for whoever to explore themselves, and get in and immerse in the passion that they can find within them. The definition of leadership is also important, the level, local, regional or global.
In a situation, where the followers have more "education", then the leadership value will get discounted, if s/he does not have education. At least to the degree where other leadership characteristics would be able to compensate for the lack of education.
I cannot discount the value of education. Not only do you learn more about your field but opens networks that enhance your portfolio as well as curiosity to understand the inexplicable. At least with a degree it introduces basic theoretical concepts, challenges you for more it also sharpens and refine common sense where most people operate from. Some people are intimidated by books and how on earth will they improve their God given talent to open opportunities for others without intimidation!