Let me address your two cherry-picked examples though. Lady Gaga is overrated. Without the aesthetic (which is an amalgamation of many creative energies from different backgrounds), she would be another formulaic pop artist. Sorry to any Gaga fans, but her music is not that interesting on its own. She's no Björk or Nina Simone or SOPHIE. Her time at an "elite private school in Manhattan" apparently didn't teach her how to color outside the lines. Give me the name of her magnum opus and I will gladly stack it against any number of great albums, both indie and mainstream, from the past 10 years. She won't fare well.
Spike Lee is a more interesting example. I love Spike Lee. He does come from a relatively well-to-do background. But you have to admit, the subject matter of his work tends to focus on disenfranchised people and communities. We also can't ignore the racial prejudices of people in Hollywood that may have made his story a bit more turbulent. I'd have to look into this a bit more but I'm willing to bet it's not as simple as you think.
Final note, I apologize if any of my arguments here have come across as insensitive. I believe that personal struggle plays a huge role in the creation of important artists and creators but I absolutely do not see that as a valid excuse for social injustice. My original point was only targeted to OP's post. The Yale professor mentioned in this article and the students calling him "disgusting" are largely insignificant in my view, and I considered it a waste of a click (especially considering NYT only gives you three free reads a month).