Exactly right. There are already properly defined rules and regulations in the Constitution of every country. These rules and regulations have been implemented by elected representatives of the people of those countries. If there is anything lacking it should be done through legislation legally. Not through private companies deciding on their own whims and fancies.

Which is why GDPR exists isn't it? Every country can frame it's own rules. Private companies must abide by those rules. Neither should they be allowed to create rules for their platforms beyond what is defined in the Constitution of the countries they operate in. Restricting speech by private companies must be made illegal. If someone says or does something wrong on social media there is recourse for it already defined by the law. Any content removal should be in the hands of the users of the platform (similar to GDPR) or the elected Government. Private companies must only be allowed to remove content that has been explicitly defined as illegal in the constitution of the particular country.

For everything else they can enjoy immunity from being liable for whatever is posted on their platform. Liability is always with the end user of their services. That way, there won't be any extra burden on these private companies to moderate content.