Couple things.
I never thought in a million years that Sterling would fold so fast but neither was I aware when this all first went down that the man was 3=5 years into Alzheimer's and was already deemed mentally incompetent to make his own legal decisions.
And I want to preface this comment with the comment that I am in no way defending Sterling for what he said.
But, I cared for my grandmother the last 7 years of her life while she went into dementia. That woman never once utter a single racist world or ever had racist feelings but near the end when she saw one of my best friends in the house, she asked what the negro was doing walking around her home. She also constantly, in her mind, lived in the 1920's and 1930's even though she was actually living in the 2000's.
This might explain some of what came out of Sterling's mouth that day, though given his past, probably not.