Greetings, fellow white man! I come in peace.
The first six or seven times someone told me I had no right to an opinion on a subject because I am a white guy, I was furious. But after a while, my feelings receded to mild annoyance. Is this kind of reply fair? No, but in comparison to the kinds of injustices endured by marginalized people, it's pretty minor. Remember, if you want to avoid this kind of abuse, all you have to do is stop reading and writing on pages like Medium. Marginalized people have to live with this kind of bigotry all the time, and have no way of escaping it. Consequently, they are going to lash out at us every so often, and if you want to participate in these conversations, you have to put up with it.
I personally feel that it is possible for a privileged person to make important contributions to these discussions, if we learn how to be aware of the ways that our privilege frequently blinds us. That's hard work, but there are also certain kinds of blindness that come from being marginalized. If privileged people do nothing but grovel every time a marginalized person with a blog gets pissed off about something, we are not going to come to the full truth on any of these issues. We privileged can sometimes come up with something to contribute, but we must show marginalized people the respect of critically responding to their arguments.
Unfortunately, rational argument presupposes a shared range of common experience, and that shared experience is not present in discussion between the privileged and the marginalized. Arguments that look rational to us can actually be quite clueless, ignoring realities that are obvious to the marginalized. That means we need to do a lot of listening before we start talking. Some of what we hear is going make us uncomfortable, and some of those uncomfortable assertions will be true. As we listen, it will take a long time to make an intelligent distinction between baby and bath water.