What to accept as fact
What to accept as fact is the primary issue in User_talk:Juxo right now where someone believes a sysop power structure must make this choice and put "non-factual statements" into a separate Opinion Wiki while the "approved facts" are respected in the Research Wiki which is on the fast-track to be seen by the public in the Publish Wiki. It does not seem that such a scheme can ever be made objective or simple.
Trolls advocate that factions have ways to combine edits, votes and bets in such a way that only information that the factions can agree on gets through to the Publish Wiki. This might involve a revert currency or a system of real world campaigner commitment to demonstrate the bodily truth, i.e. that there is some body asserting the truth of the allegations, etc.
Lawyers, the opposite of trolls, will argue that even a no body like a corporation enjoying corporate privileges should be able to use libel chill and "interference with commerce" laws to silence or marginalize an ethical minority that wishes to make it hard or impossible for the advertising and persuasion process to represent products falsely.
To a troll, a fact is what someone bets their body on. To a lawyer, a fact is what the client has paid them to claim is a fact. There is no middle ground. Only one of the who choices provides any moral purchasing potential at all.