People make fun of it, but this is why some people feel the need to say "I'm not racist but..." because they know certain comments will probably be taken the worst way possible if it's a touchy subject (like discussing a huge percentage of children growing up w/o a father in African American homes by social workers or something) so they feel tempted to use that "preemptive" strike. I saw a comment on Reddit once about that issue and the guy said "btw I'm a black man" and many people noted "dude, you just saved yourself a ton of downvotes by saying that" so you're not wrong in suggesting some people would need/want a caveat like that. Unfortunately.