How can a "brilliant" mind create a massively popular phenomenon, become a billionaire and be unaware how it is being used and by whom?

The Zuckerberg created Facebook. He didn't KNOW how it was being used or by whom despite being paid in rubles for some of the things?  Seriously. Can one have a bifurcated brain?. One side a genius the other a doofus? I dunno. Do you?