>Instead of trying to fix systems originally designed for marketing, why not actually design systems meant for disseminating and checking information from the ground up? I bet that would look way different compared to twitter or facebook.

There's a solution for this, based on prediction markets. Essentially experts make "bets" on various things and are rewarded for correct predictions. The more correct predictions they make, they more "points" they have to get their viewpoints broadcast. And conversely, quacks and charlatans that cannot model the world scientifically make few accurate predictions and get drowned out.