Three things:

1. That she has promoted so much “woo woo and deceit over the course of her career - The number of charlatans, the amount of medical quackery, and the myriad fictional narratives that she supported (and still supports) is obscene. Since Oprah is not an unintelligent woman, it's clear that she knows (and knew) her guests were questionable, and simply doesn't care.
2. Her obsession with her privacy - Everyone who has ever worked for Oprah Winfrey has signed a brutally strict nondisclosure agreement which prohibits them from discussing her without her permission, and which apparently extends for their lifetimes. Since there doesn't seem to be too much for Winfrey to “hide, the need for such draconian NDAs is itself rather disturbing to me.
3. That her ego is really so vast - A magazine with her face on the cover EVERY MONTH. Her own television network that her programming plays a huge role on, years after she “retired”. Numerous advertisements and commercials pitching products when she's already a billionaire, and has been for nearly 20 years. I'm shocked at how much of a narcissist that she is and apparently has always been. How much attention and adulation is enough?

https://www.reuters.com/article/us-brazil-crime-faith-healer/brazil-miracle-healer-profiled-by-oprah-to-face-rape-trial-idUSKCN1P321T

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