I'm not sure if its the software or the OP who added the "?share=1" parameter but thank you for including it in the link.
The flag makes reading quora possible. If HN doesn't add this parameter by default I think it would be a worth while upgrade to the site.
Lots of great content is locked in quora otherwise.
quora defends the design by saying that it's their way of piping user-specific content.
I agree, it's super irritating and results in information being locked for those that don't know how to go around it.
Quora has the opportunity to do the same, but I think the specific stack exchange communities offer a better partition between topics. Quora does it's best to show you targetted questions/comments, whereas StackExchange sites just throw you wherever you showed up (which, if by search, is usually a better choice)
A good example : I once answered a fringe question about the Dalai Lama on Quora, now many of the questions i'm tasked with giving answers to are spiritual in nature, and of absolutely no interest to me. It's the same search bubble problem that YouTube/Google runs into occasionally. Things like that make me prefer more 'basic' sites like StackExchange networks.
This is all pure speculation, but I wouldn't be surprised if Stack Exchange's RPU would be 10x Quora's.