Just to add to what @zscaler said about some white individuals fundamentally not viewing black people as equals or respecting their lives, here is a quote from one of Emmett Till's murderers:
Well, what else could we do? He was hopeless. I'm no bully; I never hurt a n in my life. I like n—in their place—I know how to work 'em. But I just decided it was time a few people got put on notice. As long as I live and can do anything about it, n* are gonna stay in their place. N ain't gonna vote where I live. If they did, they'd control the government. They ain't gonna go to school with my kids. And when a n gets close to mentioning sex with a white woman, he's tired o' livin'. I'm likely to kill him. Me and my folks fought for this country, and we got some rights. I stood there in that shed and listened to that n* throw that poison at me, and I just made up my mind. 'Chicago boy,' I said, 'I'm tired of 'em sending your kind down here to stir up trouble. Goddam you, I'm going to make an example of you—just so everybody can know how me and my folks stand.'
—J. W. Milam, Look magazine, 1956
It's just proof that the old tired "I like black people, I've never hurt any in my life, etc." trope has been trotted out for decades in the USA by racists who try to paint themselves as being reasonable members of society.
It's a power struggle of putting 'people in their place'.
This woman's thinking is an 'ameliorated' version of Milam's thought-process. She doesn't mind black people...in their place. But if there's a need for her to assert her power, then she will use a person's ethnicity against them. It is absolutely despicable.
I guarantee that this is a deep-rooted racism within her that has absolutely shaped the way she has interacted with her colleagues and clients in the past, even if she has tried to come across as nice and reasonable to them - a veneer of 'not racist'.
It's the type of racism that can only be destroyed if people take the time to be fully honest and reflexive with themselves - to question their own assumptions, thought processes, behaviours and recognise that these may need to be changed. Very few people seem to have the willingness or strength to try this, as exemplified by some of the comments on this thread.