I think that may have been true once upon a time, but I have noticed many games start using some serious bass in the past few years. Bioshock, Rage, Blur, to name just a few. Plus their bass is quite cinematic, which is much deeper bass than what dubstep is mostly using. I suppose if one had to choose a system strength, for dupstep you would want big output from 40 hz and above, and for games and movies, you would want to go for deeper bass extension at the expense of output if need be, down to 20 hz if possible. Of course, it's best to just get a system capable of both big output and deep bass, but that is expensive for most folks, both in money and floorspace.