He has given multiple live presentations on the Midjourney Discord server. He's quite happy that his work is helping lots of people make great new art.

I think its just a meme from users seeing his name in other prompts. In many cases it's used in combinations with other artists whose styles aren't at all similar, it doesn't make sense other than users spamming it to get "good" results?

Isn't the data set lifted from Artstation for a lot of this stuff?

https://www.artstation.com/Rutkowski He's a fantasy concept artist, not a like wikipedia page having artist.