I've recently been reading/watching some videos and writings by Robin Diangelo on systemic racism - here's a great starting point: https://www.youtube.com/watch?v=h7mzj0cVL0Q. She also wrote the book "White Fragility".
Thinking about that, I'm just wondering how different it would be if one of those people who mistook the employee for the CEO instead turned to the CEO and said "I'm sorry, please excuse me for the instance of racism I just perpetrated against you, I promise it won't happen again." I realize how outlandish that may sound writing that out, but I'd propose that the fact that it does sound outlandish is the main problem. Everyone in the US was raised in an environment that inculcated certain racial ideas, subconsciously or not. We can't address them if we're so embarrassed by their existence as to pretend they don't exist.
That doesn't sound outlandish to me at all. For what it's worth, it doesn't have to phrased in a stilted manner like that. A quiet "That was racist and I have no excuse. I am sorry, and will do better in the future." is fine.
I suspect that most people who want to "get the hell out" rather than apologize for racism have little to no experience with making sincere apologies and trying to genuinely mend fences in general. This probably has a significant overlap with people who claim that you should immediately leave your employer rather than speak out about any of their policies that you disagree with.