The key feature of totalitarianism is strong state control. (Evidence: see a dictionary.)

That is too narrow definition. Totalitarianism is a mindset, the belief among its adherents that "every last vestige" of their pet peeve must be eradicated at any cost. Cancel culture is totalitarian without any state control at all. "If you're not part of the solution, etc." is totalitarian because anyone can be accused of doing too little and, therefore, still being part of the problem, as I explained in my linked article about the duty to rescue. Here's a totalitarian joke.