Both singer debuted as pop-soul singers, both singer grew up listening to pop-soul (Diana, Aretha, Michael). I don't see how either of them "sold out".
Whitney seeing as though she was the exact opposite of what she protrayed herself to be. She was a ratchet home girl, but was pushed as this likeable All American sweetheart. That's why black audiences would boo her during the Whitney era. I at least think Mariah was more genuine in front of the camera plus she wrote her own music soooooooooo she was more realistic with her depiction of her reality