Freedom of speech is a constitutional right in many countries. But nowadays, several social networks "which allow freedom of speech" are appearing and growing because several of the main social networks don't allow content which is against certain ideologies. Certain theories or statements of certain ideologies are taken as true, and they can't be discussed because when they are, accounts are suspended or banned under violation of "community standards" and things like that. My question is, can any social network manage their own rules and declare that certain ideological/political ideas can't be discussed (but you can talk in favor of them) . Dont these "community standards" violate freedom of speech?
Let's look at the Ur-example of a free-speech law, and the most wide-ranging, the First Amendment to the Constitution of the United States of America. It says (my emphasis):
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
This limitation applies only to the government. Indeed, it has been argued that this limitation only applies to the legislative branch of government and not to the executive (except when exercising legislatively delegated power) or judicial branches. Certainly, the courts have held that it is within their power to issue "gag" restraining orders.
Notwithstanding, it imposes no restrictions on how non-government actors can limit your free speech. The owner of a shopping centre can require you not to evangelise, the owner of a stadium can require you not to use offensive language and the owner of a social media platform can restrict your speech in any way they wish.
You have a right to talk - they have a right not to give you a platform.
In every country with constitutional protections popularly termed "freedom of speech", that refers to limits on how government can restrict your right to express yourself. It never refers to a right to be provided a platform, nor does it ever mean that a person or organization can be compelled to express a particular viewpoint. Thus you cannot be forced to express a viewpoint that you find repugnant, and you cannot be forced to listen to ideological lectures. Community standards in social media are in fact the concrete embodiment of the idea "freedom of speech".