Correct me if I'm wrong but I believe you thought I meant left/right bias, I was looking at this from the lens of Facebook being a global platform.

To expect an even response across all political parties across all governments by the metrics they gave around incitements to violence and danger to the public is a bit unrealistic.

Bias can easily be introduced in every phase of these cases being accessed. Arguably, long before the political and activist leanings are considered.

From that it's not to difficult to see it being extended to other groups.