Ending up with a "liberal facebook" and a separate "conservative facebook" seems like the worst possible outcome. It will just reinforce tribalism, and destroy any remaining resemblance of a commonly trusted source of truth. There will be two sets of economic indicators every quarter, and both will be wrong. At that point, political discussions will just be fan-fic.

The root of the problem seems to be a large fraction of people opposed to either the existence, or at least the possibility to adjudicate, truth: "Some people say the earth is round(ish). Others say it's flat. Who am I to judge?"