There's an entire generation of customers that have never flown on a turboprop, and an older generation that could be convinced when you show them how nice it is compared to the CRJs and 145's they regularly fly on now. Plus the younger generation actually tries to care about the environment. It wouldn't be a hard sell. I used to fly the 1% around and they happily hopped in a (quiet, comfortable) turboprop when it made sense. You throw someone who regularly flies on a 145 in a next gen turboprop and they'll be in heaven.

People willingly fly airlines where they have to pay $25 to bring their backpack on board and spend 3 hours with their legs crushed against the seat in front of them if it saves 10% on the fare. They will fly on turboprops if you make it attractive.