I agree, but I think there is a solution that can help us all ask for and fight for proper discourse.
Alt-right and social-justice warriors both have a hard time rejecting objections from people with the right identities. If we created tools that helped crowdsource finding issues in their action and then identifying persons in the crowd with the right identities to highlight those we would be on the right path.
If the crowd in addition to this approach advertisers on the platforms they use to further their message, then we would also reduce their capability to scream loudly.
No leaders, no celebrities, no talking heads.
Both groups are pretty sure that the core of their beliefs is valid. Maybe fact A is false and fact B is overblown but sum(A, B, C) is still a vector in the direction of their faith. So debunking their statements won't lead anywhere.
You are much better off agreeing to disagree and trying to discuss a middle ground. But that's not what happens in modern society.