Could you expand?

If it’s “will lead to flames and reddit is happy with that, HN, not so much”, sure.

If there’s another possibility I’d like to learn it. These days I think my flame barrier drops down before I can think of other things :-(

From the HackerNews Guidelines:

What not to post: "Off-Topic: Most stories about politics, or crime, or sports, unless they're evidence of some interesting new phenomenon. Videos of pratfalls or disasters, or cute animal pictures. If they'd cover it on TV news, it's probably off-topic."

and a little further down: "Please don't use Hacker News for political or ideological battle. That destroys the curiosity this site exists for."

What if people could downvote articles, but it would have no visible effect, only advising moderators?

Or, just track how many downvotes and flagged comments are in a thread and kill anything (the whole thread) that gets even minimal controversy?

If everything that is basically redundant with Reddit or other aggregators was deleted, I think it would be like 60+% at this point, but why not go ahead and try it?

Enforcing "high quality" discussion on low quality topics is manifestly a complete failure.