I would argue that the prohibition of dueling has been highly effectively, given how the practice is virtually extinct today.

The prohibition of dueling in particular is highly effective because dueling is no longer seen as an aristocratic practice but rather as a barbarity of the past. Today, nobody gains any honor from winning a duel. When William Burr shot and killed Alexander Hamilton in their duel 200 years ago, it ended his political career, because by then dueling had already lost its prestige.