OP: Who is going to carry folk music on?...Where are the young singers, musicians and groups?

It takes three: Producer-artist-consumer. The genre really doesn't matter.

The task of picking 'it' up and carying 'it' on is, mostly, up to the consumer. Typically not the same lot for cutting edge new, mainstream pop and comeback/revival evolutions.

If they live long enough, even major mainstream artists like Bob Dylan and Paul McCartney will spend the second half of a lifetime trying to (re)fill their own shoes.

PS FZ: The Persuasions