Up is subjective and arbitrary. It implies that there is a strict and clear hierarchy to oppression, discrimination, and marginalization and ignores intersectionality. If a black woman is shitty to a disabled white woman, is she punching up or down? How do you weigh the different traits that lead to marginalization? Who's above who? How does this change as conditions change (for example racism in China vs racism in America). And in the end, what goal is it helping you achieve? Is it an effect strategy to achieve that goal? In the end, there is a more complex situation at play here that can't be boiled down to "you're above me so it is okay for me to be shitty to you."