This is just a silly red herring - the two issues are not mutually exclusive and addressing the one does not detract from addressing the other. Can someone help

This is just a silly red herring - the two issues are not mutually exclusive and addressing the one does not detract from addressing the other. Can someone help me understand why people think that thinking this way is productive, or intelligent, or… anything positive? I truly do not understand it at all. On so many articles the top/highly rated comments are just variations of ‘oh, but this other thing is even worse!’ Why is that?