The simple unfortunate answer is that different people want different things in a forum.
Some people value a very level-headed discussion forum where discussion is focused on the forum's subject matter and isn't allowed to deviate much; think of this like maintenance of a bonsai tree.
Others want a forum where almost anything goes, as long as it's tangentially related to the forum's subject matter and there are no outright illegalities or blatant flamewars. Think of this like the forestry service. Intervention is only uncontroversial in a catastrophe, like if a non-native invasive species is brought to the area.
It's an dilemma I think every forum struggles with. There are upsides to both approaches. The first approach has a unique problem in that forum members can't see what's going on as much and therefore can't comment very accurately, but that doesn't mean the first approach is objectively worse.
“The egg hatched...” “...the egg hatched... and a hundred baby spiders came out...” (blade runner)
“Who are you?” “A friend. I'm here to prevent you from making a mistake.” “You have no idea what I'm doing here, friend.” “In specific terms, no, but I swore an oath to protect the world...” (continuum)
“It's a goal you won't understand until later. Your job is to make sure he doesn't achieve the goal.” (bsg)