Hearing “I hate men” shouldn’t make men stop being feminist. Hearing “fuck white people” shouldn’t make white people stop opposing racism. Your opposition to oppression should be moral, and immovable.
Correct, and it is. However, there is a very wide difference between agreeing with feminism and Black Lives Matter in principle and signing up to be your personal punching bag. Even if I know your anger is justified, there is a limit to how much I’m willing to take before I walk away from *you* personally (if not the movement in general), especially if a) I’m not married to you, b) I’m not related to you, and c) you’re not dying from a life-threatening illness like cancer. Because frankly? If you’re not strong enough to focus your anger on the real threats — like, say, the racist misogynist who’ll be taking office in January, as opposed to Facebook drama — you’re likely to be more of a liability in the coming battles than anything else.
Maybe we’re working under different definitions of what “ally” is. To me, “ally” just means someone who’s firing in the same direction as you and who (most likely) won’t shoot you in the back at the first opportunity. It doesn’t mean I have to like you. Or vice versa.