My wife works in advertising, and we get ad-type publications, like Communication Arts, etc. So we saw the trend toward b&w and the grainy film look coming a long time ago. As a photographer, I was seriously distressed to see so many pictures in galleries with the "contact print" edges showing, or the little Hassy notches ever-so-subtly evident. And this was ten years ago, before film began its recent decline. The cachet of authenticity of b&w film seems to go back to around the time Starbucks and Pottery Barn got up and running. It was only twenty years ago that b&w fine art prints started to be considered by the wider art buying public as worth investing serious money in.
Cultural innovation is always co-opted and followed by gentrification. The real bo-hos paint in agony, strung out on heroin and caffeine in their SoHo lofts or on the edge of the Mission District, not making the rent, not getting the attention of the galleries, and then when the mainstream catches up with their vision, the Range Rover crowd moves into the neighborhood and exalts the artist's contribution and the cycle starts over somewhere else.
The longer I look at the way the world seems to work, the more I think Deepthroat had it right: "Follow the money."