You can tell them they are doing a shameful job or that you disagree with their actions or whatever.
You just can't _insult_ them like a 6 year old on a playground. Why is the ability to do so valuable to you?
It is viscerally against my cultural upbringing for the government to make illegal a verbal insult, it seems like an incredible overreach. I'm genuinely culture shocked hearing this. I'd be no more shocked hearing that it's illegal to dye one's hair.
The first thing you described is an insult.