As someone who has spent three years working with kids who grow up in economically disadvantaged situations, I have to say that it takes more than parental encouragement and talent to be able to qualify and successfully complete a high level academic degree. There are so many obstacles for kids growing up in economically depressed areas. Anyone who survives the environment of growing up very very poor is ten times more valuable as a member of society over someone who was "legacied" into a university.
When people like the Obamas or any of the other successful people who grew up in disadvantaged situations actually make it, they inspire many more people who are currently struggling to keep fighting until they accomplish their dreams.
A big motivator for me to get off my couch and chase my dream was because of my experiences working with these kids. Many of them are so talented and work so hard in spite of the difficulties they face. It made me realize that I had no excuse to just sit by and watch somebody else build my idea.