Something a lot of white people don't think about is this:
A few weeks ago I refused to allow a Black man to hold the elevator for me. It wasn't possible for me, with my heavy cart, to get into the elevator without physically brushing up against him. So I politely asked him not to.
He screamed at me and called me a Karen and screamed about how he had just tested negative.
Because, unfortunately, what I did appeared racist. It looked to him as if I was pointedly avoiding him because of a specific fear that Black people are more likely to carry COVID-19. Which I'd imagine a lot of white people do think. He had no way of knowing, none, that I would have asked anyone to move and certainly no way of knowing that I'm more worried about carrying it myself without knowing it and giving it to him.
I'm still trying to work out how I could have handled it better. The fact is that I'm having to be "afraid" of everyone right now and there is no way to prove that I'm not being more "afraid" of Black people. So I'm trying to work on techniques to mitigate it.
The point I'm making here is that the Black person who has just met you does not know you and if you come over as racist, you are racist despite your intentions...because you brought harm to somebody because of the color of their skin.
And we all need to work on how to better communicate that we are not singling Black people out when we, say, refuse to shake hands with *anyone*.