Do you feel like controversial subjects on HN are allowing dissent?
If a post about climate change, death penalty, abortion, womens rights, vaccines, etc is posted?
Going with the first one, especially in context of google banning climate deniers recently. Do you see anyone from the climate denial crowd being allowed to comment?
In my experience you're not allowed to discuss denial. You will be called a climate denier or other unflattering names and them removed.
The approach to avoid flamewars is to ban dissent and not the attacks. If everyone agrees with each other, you don't get flame wars.
The obvious problem is that you also don't get discussion.