I'm actually glad to see the conclusion. Everybody wants to censor what they don't like. There are people who believe free speech is not the ultimate value, but rather to protect people from 'harm'. In this case 'harm' being ideas they don't agree with. The best stance is not to take a side, but to make sure both sides are civil in the expression of their beliefs.
Just because a belief is civilly expressed does not make it less harmful. For example: people casually believing that the Sandy Hook shooting was a conspiracy drummed up by the government is actively harmful to the families affected by that tragedy. What do you say to those people? How do you solve that problem? And how do you define 'civil'? Because different platforms have different ranges of civility as well.
That's not a problem that needs to be "solved." It's not necessary to force everyone to think alike, or believe the same things. It's not necessary - or desirable - to try to force everyone to never think/believe mean things or unhappy thoughts.
It's similar to saying: how do you solve people that believe in ghosts or god or unicorns (particularly if you're an atheist and believe that's all bunk). Consider hardcore religious people that believe most people are going to burn in hell, and or they believe that most dead people are in hell. Now ask the same question: isn't that offensive to those people that are going to supposedly burn? Isn't it offensive to the memory of the dead? Solve what, that people are allowed to believe what they want to (including offensive things)? The censorship it would require to constrain all of it would be horrific, authoritarian to the nth degree.
The world didn't end because of all the 9/11 conspiracy theories. Thousands of people died in those attacks. Yet the conspiracy theorists proclaimed that a plane never hit the Pentagon, that there were no people on the plane that crashed in PA, that all the Jews stayed home that day, and so on. That doesn't need solving, people will never stop believing and saying crazy things, you can't force it to end.
As longer duration examples, JFK and the moon landing conspiracies persist five decades on, and will never cease to exist. If NASA couldn't solve that with 50 years of education and the extraordinary amount of evidence they've provided, what hope is there for the other items.