I don't know what it is but if you think about it the only genre of music that has lasted through out the years is the metal. This might be a little biased but in all honesty I think that it has since there has been many other genres through the years and yet in the end they fall or just become unpopular cause of the day and age. Metal on the other i see as a genre that can be played anywhere in the day and age well mostly anywhere. Things such as Electronic music has already been dying at least now you can see that there is less and less searches for this type of music. I enjoy many different types of genres i just don't think that they can surpass what metal is today in the sense that it has one of the largest followings of people then you see how Pop music now where it has started to become popular but i doubt it will ever surpass what metal is. You can even tell by the concert that Bands have i mean look at one of the most popular rappers today and then you look at the concert of one of the most famous metal bands and you will see that there is a significant larger amount of people in the metal bands concert than there is in the rappers concert