Earlier quoted context omitted.
They're not wrong in that people often rationalize their 'instinctual' choices, but to imply that nobody is cognizant of any of their thoughts or biases and that we're all slaves to our lizard brains is a bit of a stretch.
There is a TON of data out there demonstrating we all have subconscious bias. Moreso than we believe. Even of our own groups! We are slaves to our brain! This is a good summary of some of the data: http://www.cnn.com/2014/11/26/us/ferguson-racism-or-racial-b... Professors at the University of Chicago and MIT sent 5,000 fictitious resumes in response to 1,300 help wanted ads. Each resume listed identical qualification…
Many people are consciously racist, not in a "I want them all lynched" way, but in a "meh, I'd rather not meet with a black guy, probably a waste of time" way.
Of course they aren't going to admit that sort of bias. And again, you're just guessing at what happened.
There is indeed subconscious bias, and it rears its ugly head when we're observing people's mannerisms, their speech, their attractiveness, and yes, their skin color. But just looking at names on a resume, I'd argue the decision of calling someone back, based on the stereotypical application of their first name, is just a conscious bias.