I agree a big company shouldn't have _complete_ power to control content on their site for reasons the OP says because at some point this becomes a danger to society. At the same time it is a danger to society to freely let users promote whatever content they want, for the same reasons.
For all the examples or people who have been persecuted (or whatever word would fit better) for saying the "truth", like scientist who said the earth was not at the center of the universe, there are countless others who, for the better, were quieted from issueing harmful information.
The OP says people should be taught a lesson in critical thinking, but I don't think this is a problem. I think most people are pretty logical, they are just dealing with misinformation, no matter what "side" they are on.
So this is a real problem. It is good the OP raises these questions, but I don't think it has the solution.