Yes, andrewljohnson agrees about that. However, his point is:
>Linking to copyrighted material should not be illegal
And I have to concur. This should not be a copyright violation.
1. Copying a news article is likely to be infringing, but it might not be; it's always worth considering whether it's a fair use, especially for very factual material. 2. More importantly, it's not that HN would be liable "by default". Without the safe harbor, they would be open to claims of secondary liability, but the copyright holder would still have to prove the elements of contributory, vicarious, or "inducement" infringement.
Again, still worth it to be able to avoid lawsuits or at least dispose of them at an early stage, but the risk isn't automatic, full liability for the hosting site.
The DMCA policy and registered agent gives a content creator a method to notify Y Combinator of the violation so YC can take it down. How else would they know who to contact or how to protect their rights?
If a site has a proper policy and agent (and abides by the policy) it gets safe harbor - it's not liable for the infringement. It's not an unreasonable amount of effort, and the scheme is a pretty decent compromise between protecting copyright holders rights and allowing user generated content.