that's what Producers are hired for. Moreso outside of hip-hop than anything. Although, in hip-hop your are seeing cats that where a million hats. Producer, songwriter, assistant engineer, arranger, programmer, the guy who bought the donuts etc. I think the new era of hip-hop producers are stepping up their game on across the board. So we will probably see more and more hip-hop cats playing the "Producer" roll.
But there is something to be said of Nicolays point of DIY music. This will begin to have an impact more and more over the next few years. So it'll be interesting to see the melding of all these rolls. As with anything there will be good and bad.
------------------------------------------------------------ subhaanakallahumma (Glory be to you, Oh Allah), wabihamdika (and I praise You). Ashhadu anla ilaha illa anta (I bear witness that none has the right to be worshipped except You). Astaghfiruka