Let me be clear; nothing there that you could not find by just browsing Parler.

Maybe there is a deleted post somewhere and that could be interesting but since it is not marked and there a millions of URLs it is kind of useless.

Story is that Parler didn't delete the media associated with posts once they were deleted, so while you lost access to the post's text, the video files using incremental names (eg. 1.mp4, 2.mp4 etc) meant you could download videos from posts that might be deleted.

I think the "story" here might be a bit of hyperbole as what is going on here is just an archiving of the public contents of Parler similar to what happens all the time with Twitter.