Freedom of speech is not the same as freedom of access to information though (idk if that's in any laws). That said, the basis of freedom of speech and information is that you will not get in trouble for accessing tiktok and co; it does not mean the US government or whoever has to make it easy for you. "Not illegal" does not mean "accessible". For example, a court ruled that it's legal to sell and trade digital purchases like games on Steam, but that does not mean Steam has to make it possible to transfer games to other people.

Anyway, there's ways and means around getting tiktok from the app stores - especially thanks to efforts in European law that force both Apple and Android to open up their platforms so that consumers can do what they want with their devices.