My example: https://news.ycombinator.com/item?id=21918556 https://news.ycombinator.com/item?id=21913030
Example of similar posts: https://news.ycombinator.com/item?id=21918610 https://news.ycombinator.com/item?id=21916651
I'm sure there are other examples out there.
The example you list seems new indeed. Usually there's at least a difference in URL. Or the older story is a day old (stories that didn't gain traction get another chance).
This is something for hn@ycombinator.com to check on.