Facebook can disrupt and make it difficult for a religion or sexuality to communicate or engage in culture.

They may not be able to tax or put people in jail directly, but with lawyers, lobbyists, and DMCA takedowns they can achieve similar results.

They can hire lobbyists to affect government policy like immigration, environmental protections, and war.

I'm less concerned about what happens if Facebook fails than what happens if Facebook succeeds.

Note: "Facebook" used as a placeholder for any mega-corporation.