I agree they are great resources Bart. The problem is that people have to want to use them. If you think everyone really wants to know what's going on, you'd be wrong. Reality can be depressing and when someone's world view is threatened, it causes a great deal of anxiety. When someone encounters the possibility that what they've come to believe might be wrong it creates a great deal of cognitive dissonance.
People who are resilient, intelligent, well educated, self confident and well adjusted will face that possibility head on, take in as many new observations and facts as possible and then adapt their world view to square with reality.
Conversely, people who are not well adjusted, or who lack self confidence, or who are not very resilient, or who are not well educated, or are perhaps just not one of the brighter crayons in the box, may not respond positively when they encounter facts that threaten their world view. They often deal with that cognitive dissonance by trying to find information, or opinions from authority figures that support their world view. They then use those alternate facts and opinions to discredit anything that doesn't support their world view. In the current vernacular they dismiss it out of hand if they don't like it or agree with it and call it "fake news". Facebook gives them exactly what they crave - so why would they bother fact checking?
The problem isn't a lack of information, or censorship, or diversity of opinion, the problem is that people who don't adapt well use Facebook to soothe their fears and get comfort in the form of confirmation bias from people they regard as "authorities", while rejecting everything they don't like. And Facebook algorithms feed into that confirmation bias.
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A forum like this is different. Here someone can throw out a theory or observation with a conclusion for comment. If they are wrong or missed something, someone will come along point out what they missed or suggest and alternate explanation. Discussion ensues and learning occurs and if it's an ambiguous issue, you'll at least see where the consensus lies.
Unlike Facebook it's a good place to challenge your own assumptions and opinions, and refine them based on the input and experience of others.