I think this is important because it feels like an endless surprise to everyone that this keeps happens. It feels like we have to cover the same ground again and again in discussions about it, and it feels like if we could tackle this problem more generally, the benefits to society at large would be massive.
Product reviews are valuable, producers capture reviewers, spam fake reviews.
Email is valuable. Spam nearly destroyed it until we migrated the entire decentralized system to Google.
Public discussions like these are valuable, and God knows how much work Hacker News does to moderate all this.
None of this feels like it's designed to resist this problem.