Sounds like a system which could easily be abused. "politeness" and "decency" are ripe for all manner of interpretations.

In the US we see that the only things keeping authoritarianism at bay is larger the people following norms (like the peaceful transfer of power after losing an election), and the executive obeying orders from the judiciary. All it takes is for a group to not to that any more and boom.

Short road to where 'slander' means any criticism (however objectively true and justified) of people in power and you get a swat team at your door and steel boot on your neck.

>That's because slander isn't protected speech and is directly illegal.

In one case it wasn't slander. A person pointed out a politician's Nazi/Stati past on social media and he still sued abusing the "muh dignity" bullshit law.