The reason is because the OG is interesting, but the native link hides its content. It is also at an interesting point in time. (the 2008 crash). And I feel this thread likely informed/formed some of HN's moderation ethos and community focus at a time when it was much smaller than today.
https://news.ycombinator.com/item?id=311049
This is a post of what the Guidelines specifically ask us to not do:
> Please don't post comments saying that HN is turning into Reddit. It's a semi-noob illusion, as old as the hills.
https://news.ycombinator.com/newsguidelines.html#:~:text=Ple...