As a white European I do find it shameful that someone uses white European 'superiority' as justification for this massacre.
I think it is wrong if anyone uses ethnicity, religion, gender, sexuality etc to meter out arbitrary violence or punishment. One poster suggested the CCP were an influence on the accused killer and the other replied insinuating white people and Australians are comparable. It is a false equivalence. One is government policy and the other almost certainly generates feelings similar to yours in nearly all of that group and the opposite of official government policy.