Its fortunate for the world that digital imagery is ephemeral. One really has to make a concerted and long term effort to preserve a digital image. The cost of preserving digital may be as much as ten times that of film [citation Richard O'Connor in interview at Phogotraphy.com ]
Sure. Film is much easier to preserve. Regardless of media, I believe the most important criteria is
a willingness to preserve the image. Twenty years from now, someone can go to their late aunt Exa's house, open up an old shoebox, look at the negatives, and decide the box's contents are worth keeping. If they open up a desk drawer and see ancient USB sticks, SD cards, or CD's - will those simply get tossed or will someone make the effort to read them?
Digital images are viewable only as long as the following is true: the data is preserved, a device exists to read the media, a software application can interpret it, and that application can create an image on a current display device.
If they make the effort to read the media, will that media still be readable (how long do USB sticks or CD's hold data)? If it is physically readable, will there be a device that can read it (in 20 years will there be a CD reader that Exa's nephew might have access to)? Although I actually do have a dual 8" floppy reader (DEC RX01), I can't expect my successors to be willing to try to find a USB 2.0 reader. Even if they get that far, will they be able to read the NEF file Exa created in 2015 with her Nikon D810?
So that's the point: to preserve a digital image over a hundred or so years
someone has to copy that image from its current media to the next new media and maybe re-save it in the next less obsolete format. Sure, it can be done, but it requires not only effort, but also requires will. It's a lot easier to put negatives in a safety deposit box and be sure they'll need no long term maintenance.