This requires a more collective approach in order to be effective, of which this likely not happen because the internet will always be open for everyone, good and ill-intentioned, the reasonable and discord-seeking. And those who just want to see it all, ready with a pack of popcorn, subtly adding fuel to the fire as well. Drama's one of the oldest form of entertainment, after all.
Personally, I'd rather see a more heavy-handed approach from the forum owners myself, with a stricter moderation and punishments that also tranfers to your gaming account.
Because if you let those people free reign and 'just' ignore them, you empower those to keep on going as they think they won with their 'argument'.
And sometimes, just like in the real world, harsh consequences need to be in place. Even when it means drop-kicking them (figuratively and literally) in order to keep them in line that their nonsense is not welcome nor tolerated here.