Yeah, that shit is so fucking dumb. Being able to solve one quickly is a cool skill, id like to learn that at some point. But complete mastery isn't even very complicated. After you learn all the algorithms, which I'm sure for a 4x4 is WAY below what the human mind can achieve its just a mechanical pursuit. The only way to add challenge is increase the number of squares.
Being really good at something involving changing circumstances or something versus an opponent is much more complicated than cubing.