I do not understand the appeal of watching another person play a game, while doing idiotic commentary. So yeah, why do these videos get so many veiws? (Btw just graduated yesterday, most boring three hours of my life )

Congrats on graduating from whatever you graduated from!

People (including me sometimes) find these videos funny when the people doing them have "interesting" personalities - plus, horror "let's play" videos are popular as the reactions to jump scares and terrifying scenarios are hilarious to view.

I think for some people it is convenience. They don't need to buy the game and just have to watch it.
For me it is sometimes after i played a game through i must watch other play it and see how they find things. But it is better if it is completely Blind. When i was fascinated from some moments in a game it feels good to see how other people see that and maybe have the same reaction. You can watch it over and over again and when you know whats gonna happen it is fun. When it is not Blind it is kinda boring sometimes because it is contrived. But maybe some people watch it still. To not play the game... or just the first minutes to look if its good and stuff. But I know what you mean with that, lets plays are everywhere and like an big phenomenon. Sometimes it is about the game and sometimes they just wanna talk. It feels like two different kinds of lets play exist.
1. Wanna play the game and say sometimes how it is.
2. Wanna talk the whole time and play.