Like it does now? With some content paywalled and some not, and perhaps some links rejected from the submission form if the link has attributes indicating a payment is required. I will concede that adaption would be required, but I disagree with the idea that this model is entirely unreasonable.
When Hacker News users link to paywalled content, some of us consume it without issue because we pay those sites (Bloomberg, WSJ, Economist, etc).
No, it would not exist because ycombinator makes no revenue and can't pay anyone.
Yeah Hacker News would likely have to shut down if targeted by bills like these.