with regard to your examples, Kim, I'm neither offended nor in agreement with them because they are simple one line sentences, devoid of any actual context. Depending on the context, I may agree or disagree that white people are racist, and I may agree or disagree that white people benefit from racism. It does largely depend on the context of the rest of the argument somebody is putting forward.
For example, if somebody is putting forward the idea that there is a global system of binary racism between white people and POC which benefits white people, I would disagree on the grounds that such arguments are used online to trivialise and dismiss the Jewish holocaust and the genocide of ethnic Chinese people by Japanese people (or should that be some Japanese people!?) in the twentieth century among other examples, and that it is extending out an American experience that does not fit with the global situation. It has nothing to do with the grammar or the use of some, because if they were to say some white people benefit from racism and some POC of are disadvantaged by it, it does nothing to clarify who or what situation is being discussed, and it effectively becomes a statement that isn't really saying very much at all about anything.