A spanish political party announced they are suing Twitter in Spain and United States for violation of freedom of speech after an account of them was banned. Details of which arguments are going to use werent disclosed, but I just remembered United States president was forbidden by an United States court to ban Twitter followers because his account was a government account and that would be a violation of freedom of speech to the followers. Could a social network be sued for violation of freedom of speech with the same argument, that they can't ban a government account because that hurts the freedom of speech of the citizens of a country?
In a democratic country, they cannot be sued successfully. Freedom of speech is for the citizens, not the government. And it is a company doing the banning, not the government. So the situation is totally different in two significant ways.
(That assumes laws not too different from the USA. Obviously a country might have laws that make it illegal for companies not to publish what a political party says).