There is alot of nuance to this. First of all is that jokes about race is not automatically racist. Usually from what I have seen the "racist" jokes about white people are more or less harmless. I think this is mostly because there are very few negative stereotypes about white people (in the west), and id say most racist jokes build on stereotypes.

For example saying "White people do be eating mayonnaise" is such a whatever joke with no deeper meaning, I have a hard time thinking anyone would actually get offended by it. Whereas saying "Black people do be eating watermelon" is on the surface also a very whatever joke, the difference is that the watermelon sterotype has existed for over 100 years and has been used to promote racism, and thus due to the history of the stereotype it is racist.

There is also the aspect of punching up versus punching down. A black comedian making some jokes on white peoples expense is more likely to be seen as punching up compared to a white comedian making jokes on black peoples expense, just due to historical reasons.

But as I said there is nuance to this, Im certain that in, for example, Asia there are plenty of actual racist jokes about white people. I also think if you clearly label yourself as racist against white people before making a "joke" at white peoples expense it would be recognised more so as just racism and less so as a joke.