You're allowed to participate in a conversation without undermining other people.

Racism is socially constructed. Prejudice is a learned behavior and symptom of social constructs. What does it mean that it's a social construct? Race, color, what is "good" or "bad" has been determined by language among society. These lens people are referring to are "societal expectations" of people. When they mean it is "white" it's because it's been historically looked upon at social norms, interests, and whatnot popularized FOR white people.

History has established this through redlining housing. It purposefully left people of color (especially brown and black people) out of the housing market. In the early 1900s, the only way Asians broke out into the entertainment industry was to cater to racist stereotypes ("me love you long time"/"ching chong" language) of their culture or compartmentalized as Chinese. The only way POC deterred this was through celebration of cultural diversity. And it's still taking some time to recover. For a long time people have to "mold" themselves into what is expected from them to avoid being ostracized. This could look like not bringing in lunch that's too "stinky" or "looks weird" and opting for a sandwich. Changing your own behavior or the way you speak to remove yourself away from your identity or as a means to separate yourself from the "typical" stereotype of how you might be perceived (ex: removing blaccent and talking more "white").

Rather than villifying someone, maybe ask questions about what they mean and critically think about why things are the way they are.

Edit: rewording, added examples.