I suppose his problems could be due to terrible controls but it did look like he just "mashed buttons" and didn't bother to learn from his mistakes. The tutorial wasn't super-detailed but did explain enough. I mean, we managed to figure out Megaman and Metroid back in the days with much less information than this.
I didn't watch the entire video but there was one time where I'd put the blame on poor or lazy design. Around the 9 min mark he fails a jump, lands behind the bush in the foreground and dies. The game fails to visually inform the player that merely going behind the foreground leads to death.








