In case you didn't get the memo, here is a primer on how to turn a democracy into a totalitarian system:
1. Invent an external scapegoat ('the enemy')
2. Polarize: Either you're with us or with them. Mediating center positions and compromises belong to 'the enemy'. Argue that you're for the simple, honest-working men and against the elites, who belong to 'the enemy'.
3. As part of point 2, push radical radical positions into the public discourse to erode social control mechanisms. ('Why can't I say X' where X is something despicable, like being a racist, being for for genocide, etc., but dressed into a seemingly legitimate 'arguments' and 'concerns'.)
4. Instil fear of the external enemy and, as much as possible, terror against the internal enemy on the streets. Ideally, there should be bands of people on the streets who mug or kill perceived enemies (e.g. the S.A., Bürgerwehren, death squadrons, etc.).
5. As a result of 3-4, once a certain threshold is reached, public discussion has been radicalized and mediating center positions have been quenched. Voting will become a false dilemma between us and them.
6. Seize power by vote or coup, eradicate the remaining control mechanisms, eradicate free media and put them under state control (in a fight against 'fake media'), eradicate remaining political opponents by abusing the justice system (anti-corruption laws work well).
The idea behind limiting freedom of speech is to prevent 2-3 from reaching a critical threshold that enables 4 & 5.