A totally digital world is mostly hype or wishfull thinking on the part of those in the industry. The internet provides a certain percentage of retail sales, but will never replace bricks and mortar.
I still remember the talk in the late 90s about how everyone would carry around digital books and book readers. Libraries would be a thing of the past, books could be either borrowed or purchased online and downloaded directly to your reader. One little problem though, people actually like to hold a book in their hands, like to see them on the shelf and be able to pull them down when ever they want.
Photography will become a mostly digital industry, but there will always be those who want the feel and experience of using traditional methods. As as been discussed in other articles, there is a resurgence in this country for all kinds of hobbies, activities, creative outlets that require a hands on approach.
As our world becomes more about automation and computers, the more I think people reach out to have an activity that is free from computers and printers and robotics. So I think this s one of the great saving attributes of traditional photography.
If we really care about the medium, then it is our responsibility to foster an interest and appreciation in others and help those who ask questions and are just beginning the journey.