Yes, but if you look closely all of those submissions were made on the javascript subreddit. It's entirely possible that this sub was still private on the 24th, and went public on 25th. I don't know for sure but that seems to be the most likely scenario.

Edit: Looking at the blackout tracker, javascript was still private on June 24th, which is the day that the OP of the video was manually deleting his submissions.

I don't think they are actually restoring posts/comments. This whole thing is based on confusion about the blackout and many subreddits going private. Most people would think you can see all of your own posts and comments if you are logged in and go to your profile page, but if a subreddit goes private you cannot even see your own submissions in that sub.

So after the blackout ended and most subreddits went public again, people who nuked their account history are now discovering that there's still posts remaining. They think these posts were restored, but they weren't even deleted in the first place.

This is obviously a huge oversight on how Reddit handles your data and your profile page, but don't attribute to malice which is adequately explained by stupidity.