People are too distracted with "life" and the majority don't even bother thinking for themselves, so therefore barely any new ideas emerge. The way our world has turned out, people are struggling to support themselves and live in general to spend time thinking about things like this, not only that but it is also easier to simply mash things together. Big companies like the record labels would rather spend money on something they know will sell to the masses and bring them profits rather than take a risk with an unknown band.

Real musicians are constantly having to create, not the prepackaged music you get in mainstream but metal and such. Originality in art is big also. All the great movies are original thoughts and creative creations. And books etc. There are still new ideas, I get them all the time, but unless you are in a position to use them they will never see the light of day. Our society no longer values originality and creativeness, but efficiency and profits.