They aren't bots. The videos just hit numbers that good. Videos with similar ideas (thumbnail and title wise which is the most important thing on youtube) have proven to hit similar numbers long term. For example, the video he did recently where he throws a train into a pit was done because the concept was proven to do well years ago virtually. Doing it in real life was an easy way (for him at least) to expand on that idea.

Proof:

Old video from two years ago (look at the thumbnail and title)

youtube.com/watch?v=gaXkhN6aVxI&

New video that mr beast did

youtube.com/watch?v=fuhE6PYnRMc