This all sounds good, but if I assert that the earth is flat on Facebook why shouldn't that simply be labelled false so others can avoid wasting their time trying to refute a ridiculous assertion? And if you agree with that, all we're arguing about is where to draw the line between "obviously false" and "disputed" facts.

> It becomes necessary when you lie all the time.

There are plenty of people lying and/or grifting on the other side of this power structure as well. There is some non-zero benefit being provided by fact checking, but it's certainly not an ideal situation. The real problem is virality. No one felt the need to fact-check discussion forums because those posts were not likely to spread to millions of people.