Well, who are you to speak about this, as a self-appointed "white guy"?

Are you Jewish? And Irish? And Italian? And Polish?

Are you Mormon? Catholic? And a New Atheist?

Do you have a strong accent? Is American culture new to you? Are you a recent immigrant?

For that matter--are you black? Are you a traditionally disadvantaged minority? And are you also white? If not, how the heck do you know what it's like to experience "racism, institutionalized or otherwise"? If you haven't experienced it, how do you know whether or not it's enough like other experiences to have anything to contribute?

You're going down a really unproductive (and illiberal, and society-destroying) rabbit hole here.

If you want to admonish people to talk about what they know, and be ready to learn about what they don't, that's great!

But the presumption that you know, because you're white, what other white people can and can't learn about, and what other experiences that you haven't had do or do not require one to mute oneself is both arrogant (some might call it "whitesplaining") and completely contrary to your own message.

Society is a collaboration between its members. Just like in marriages, where poor communication bodes ill for the long-term prospects, so too does poor communication between all the members of society bode ill for the society and/or for its members.

We absolutely want people to be trying to educate themselves, but then they should speak if they have something to share. And if they say something dumb, we can call them on it (sternly, if they're obnoxious; gently, if it's an honest well-intentioned mistake).

I am not sure whether your thesis here is presented obnoxiously or not, but I'm calling you on this one.