That’s not accurate to say. A person may be accused of racism due to a misperception (or even fabrication) from another person’s perspective, and in such a case that’s not “an example of being racist”.
Anyone can accuse anyone of anything; that’s not sufficient to suggest that the accused must be guilty on some level.
You misread (I think). I believe they meant an example of an event that can be interpreted as racist, even if it wasn't. Thus the proper reaction is to supply an alternative explanation.
> If you have been accused of racism that's because somebody has an example of you being racist
> any other person in the news accused of racism
You’re kind of proving the point by claiming it’s always so clear cut.
If you have been accused of racism that's because somebody has an example of you being racist. If you did not have racist intent you can clarify your intent. Simply claiming you're not a racist won't do because pretty much everyone accused of racism makes that claim (example: central park dog walker, or any other person in the news accused of racism).
Edit: I am talking about instances where the facts are not in question. For example, you did not hire Xyz, and you're accused of racism.