Oprah is a lovely person, and her speech at the Golden Globes last year was very inspiring. (Okay, I admit it, I cried.) But president? No. Just no.
In addition to her commendable promotion of reading and various humanitarian projects, Oprah has unfortunately promoted several truckloads of junk science over the years.
Roger mentioned anti-vaxxers. Guess who gave Jenny McCarthy her platform to spread
Dr. Andrew Wakefield's self-serving lies about vaccines and autism. And Oprah has given many other dangerous quacks a platform, too.
The current "the-experts-have-it-wrong" attitude in the Oval Office hasn't worked out very well. I don't think the answer is to pick another flavor of "the-experts-have-it-wrong."