Most people are not information or media literate, they don't do their own research to fact-check claims, and they believe any authority who says something simi

Most people are not information or media literate, they don't do their own research to fact-check claims, and they believe any authority who says something similar to what they already believe. The "marketplace of ideas" requires people to put in the effort I describe, effort that they clearly aren't, so the responsibility for checking and enforcing content limitations passes to the platform owner. If you don't like this outcome, argue for more humanities and social science classes in primary and secondary education to educate society in evaluating claims and the other aspects of information and media literacy.