Tums, If the sheva mitzvos bnei noach have to do with torah, then democracy fits in to #7. Let’s say it doesn’t though. Red lights have nothing to do with Torah either, but you stop at them anyways. Again, IF you live in and benefit from a country with a democratic system, you are obliged by your benefit to respect that system, including its freedoms, in the public realm.
You can choose to change that system and its standards, but to do so, unless you bring either rule at the point of a gun or an act of hakodosh boruch hu, you need to convince the others you share the country with. It has been done before, it’s not impossible. Unless you remove yourself from the environment and the society and its benefits, you don’t have much of a practical case.