Throwing out "whataboutism" every time someone dares ask a question like this is a fallacy in itself, intending to distract from the question of why genocide in places like Sudan are so thoroughly and utterly ignored and even buried.
The simple truth is a lot of, if not most, such vocalised outrage in any country is nine parts vanity. Remember #StopKony? About as effective for the people being harmed as students at Columbia barricading themselves into a building.
I’m not sure I condemn moral vanity. It is a genuine intellectual exercise. But it’s one that doesn’t particularly benefit from repeat unless one seeks to become a student of atrocity, and one that has strong viral effects.
What about the minority who actually try to help those harmed, e.g. by fundraising for victims or volunteering? They’re far and few in between. Moreover, their efforts benefit from economies of scale.
As a result, in any community, the people actually being helpful will tend to pick their battles. And the people flipping out for fun will cluster around whatever is trendy to flip out about in public.