Just like Haven said, a sub-genre within a sub-genre is possible, and there's nothing wrong with it.
So, just because it isn't mainstream, it's a bad song? Great logic there
And for you information, Mala is insanely popular in the Dubstep scene, and is considered to be one of the most important artist within the genre
One last thing, I used Bangarang as an example of how "Brostep" sounds like, and the second to show how "Dubstep" sounds like. If it's good or not, is up to you