Once you have enormous network effect like TikTok has, you don't really have any free selection of alternative apps. You are free to use one, but you will be the only sad user over there.
Regulations are needed that would force large platforms like TikTok and Instagram to enable federation, opening them up to actual competition. This way platforms would be able to compete on monetisation and usability, instead of competing on locking in their precious users more strictly.