To answer the heart of your point: any kind of editorial/screening system isn't perfect. We'll get things wrong. We always have, always will. It's still better than what's happening right now on these mediums where we know some portion of the population are "getting things wrong" and we're just allowing it to happen in a free fall fashion. "Do nothing" is never the answer, never has been and probably never will be.

To address your specific example: It's not based on what most of the population thinks. Qualified opinions are a thing. We can talk about what makes a qualified opinion, with your example or any other subject. Notably we see these types of opinions in your example gaining momentum because we're allowing certain groups of people unfettered access to an audience. It's really a bad example in my opinion, but I understand and sympathize with the point you're trying to make.

Unfiltered, unstructured information from unqualified sources tends to prey on our darker nature more often than it appeals to our better senses as people. To kind of expand on implementing practical systems around how we actually function as humans, in a lot of ways the "bad" part of human nature is why we've structured many western governments with explicit separation of powers with checks and balances. There are just some things we gravitate towards as humans that just aren't "good." James Madison in fact said the state was just a reflection of human nature, for the previous reasons. In a lot of ways, we have historically treated information dissemination in the same manner, checking and preventing the worst of our nature when broadcasting and consuming information via editorial controls and trusted, proven sources.