Pragmatically: It's important because the fact that this keeps coming up again and again suggests it's not going to go away just because it's annoying to many when it happens, and a mechanism to channel, redirect or settle the matter in the form of community norms hasn't yet been found. Meanwhile, there's clearly people who find it relevant, both to their participation in LW and not infrequently to life experiences that have bearing on what they can contribute to refining the art of rationality. Some of those people are major contributors here; some of them may still be lurking. Some of them haven't even found te site yet. A global norm that rejects the topic altogether seems like a great path to evaporative cooling in an area where LW has real potential for PR issues, and which may be a long-term impediment to its success. Restricting the topic to Discussion only (regardless of the potential quality of the post and ensuing discussion) or attempting to limit the length of threads directly seems like a bad idea.

You can always downvote it if you don't want to see it.