I'm saying we shouldn't make things substantially worse for 95% of people just to make things marginally better for 5%. Usually "accessibility" on the web means adding 1em padding around everything so that I can only see one comment at time on my 39" monitor.
The parent comment mentioned CSS changes, but I basically think the appearance should stay the same, and any accessibility improvements can probably be accomplished by changing the HTML for better screen reader compatibility, if needed.
Most of the advice on that page is about using the correct semantic HTML elements as well as aria annotations, which is what I had in mind. Basically the appearance should stay the same, but I can definitely see how fixing up the HTML could make the page more navigable by keyboard / screen reader / etc..
HN is terrible to use on touchscreens (smartphones, tablets, certain laptops) and I wouldn't be surprised if more than 5% of HN's target audience are negatively affected by it. And I doubt that many people use 39 inch monitors, certainly not 95% of the target audience.
It's not the appearance. Load it on a mobile browser and you'll see what everyone is talking about. You wouldn't even have to change the desktop version. Just have a mobile option too. HN's layout is so deadpan simple is would be incredibly easy to build a mobile interface with a modern CSS framework.
The parent comment mentioned CSS changes, but I basically think the appearance should stay the same, and any accessibility improvements can probably be accomplished by changing the HTML for better screen reader compatibility, if needed.