The thing is, at this point saying that there's discrimination and systemic bias should be about as controversial as saying that the earth orbits the sun. It's not something that should be responded to with a demand for sources, and the fact that it always is, and always devolves into people trying to shift the argument to whether there's even a problem at all (regardless of any one individual's reason for starting such a conversation, that's where the conversation inevitably ends up), is just ludicrous.

People who are unaware of the existence of the problem can use a search engine and read up on it.