Prophetic is defined in this thread as the ability to observe, analyze, and articulte what is going on in culture. Some bands see the issues that affect our national or global life and create music that slaps us in the face with a wakeup call. In my early days Bob Dylan was our "social poet/prophet." However, others have stepped up and hit us pretty hard. I thought Green Day's "American Idiot" and songs like "Minority" hit us in our collective gut. I am not offering anyone for I want to hear who you think is describing, in the late Marvin Gaye's words "What's Goin On?". Believe me, I will give them a listen.
I would think its Roger Waters. After Pink Floyd( and even with Pink Floyd--war themes and etc) his works specially "Amused to Death" has subtle hints at the consumeralization of our consciousness,with a pinch of salt-- trademark Waters.