There have been several posts about this (e.g. [1] and [2]), downweighted by user flags and by standard penalties (e.g. for politics stories). But some thoughtful users have argued that it's more on-topic for HN than most politics, so we'll make an exception, even though HN probably ought to be in detox right now.
Edit: actually there was already at least one major discussion about this: https://news.ycombinator.com/item?id=13019333, so technically we ought to be marking all these as dupes. But we'll leave this one open for now.
The moderation test in cases where there's an ongoing story and many follow-up posts is: have one major thread and bury the rest as dupes unless there's significant new information.