The Green Party would be a much bigger threat to free speech than the Democrats would be. So if the Green Party had their way, all forms of media would either be owned by the government, or some other type of collectivist institution. All decisions would be made either by the govenrment or by a majority decision. The individual private citizen would not be allowed to own any form of media. Ownership equals control.
Free speech is based on private ownership of property.
If the individual private citizen is not allowed to own property, then free speech cannot exist. Anyone who truly believes in free speech cannot be in favor of the Green Party.