That's not something that really works with industries that are zero sum games. You can't have a dozen competing rail companies in a given state because there is only so many paths that a rail system can take, and you need to clear out continuous stretches of land through eminent domain.

If a company provides a vital services and fails, it should be nationalized. If a company does not provide a vital service and fails, it shouldbe allowed to fail and the employees themselves bailed out.