What? You aren't familiar with one random guy on the internet that maybe makes some videos in a very niche market that you may have never even heard of before? What? Do you have some sort of life of something preventing from crawling every single crevice on the interwebs?
Not quite as niche as you describe. He figured out how to fairly consistently hit youtube recommendations / top videos. If you use youtube, there's quite a good chance you've seen one of his videos on the frontpage or seen his name a few times, even if you never watched them or aren't interested in his content.
This may be something you haven't considered, but there are ways of using YT with never seeing the front page. Some people don't just "browse" YT, or watch video after video after video following some algorithmically chosen playlist. It is possible to watch a single specific video and then leave the site. Just like you can also read a single tweet without infinitely scrolling through the bedlam.
I mentioned recommendations and top videos. It doesn't matter if you visit the front page - there's a good chance you've seen Mark Robber's video thumbnail, whether you browse YT for content or not.
I have a bad news for you: youtube tailors their recommendations to each person. I know! It is difficult to belive.
Sarcasm aside I don’t know who this Mark person is. Never heard of him, never seen a video from him. And I’m quite okay with that. If you were to ask me what is trending on youtube I would tell you it is woodworking videos, zany snippets from musicals, and people discussing how a windpowered car can travel faster than the wind. But I also know that that tells more about my media habbits than youtube itself so I don’t generalise from this to everyone.
I don’t know him by name but the porch pirate glitter bomb project video and subsequent controversy about the legitimacy of some of the footage was sort of front-page-of-the-web stuff for a time.
I also saw the timer arcade beating device prior. It was well done. He makes some cool stuff, but the former nasa thing and sort of YouTube pandering takes away from it for me.