Pistons and Windmills
The information is not separate from the medium because it is the medium. A photograph is a bunch of crystals that are the tone they are, the size they are and where they are on a piece of photo paper. A list of coordinates and tonal values could be written as magnetic flecks on a hard drive, holes in a punch card, ink on paper, even strategically arranged shells in the sand on a beach and the information that they represented (held) would stay in tact if you wrote it down on another medium. And someone could read it and follow those instructions and generate the same image from a grid of dots. A photo doesn't do this. You could treat it as a graphic notation of that list of dots and values but in doing so you'd be producing the information by measuring the dots in the photo and that is digitizing.
So what does it matter?
To the music and entertainment industries-- Hell, any industry that sells information, this is a complete upheaval. You see, you can't actually sell information. Information doesn't exist in the real world (The "Objective" world). Ink is ink no matter what shape it's in. Whether a coin is heads-up or tails-up matters to people, but the coin is the coin either way. Medium exists but info does not.
You can't sell a song, but you can sell the plastic that it's cut in to. You can't sell a story, but you can sell the paper that it's printed on. You can't sell a movie, but you can sell the tape that runs through a machine to generate the images and sounds.
And up to this point the entertainment industry was based on selling 2 things: 1) the medium that carried the information and/or 2) admittance to a performance of it. I'm going to put aside the latter as seats in movie theaters and space at concerts is not what the industry was worried about losing... mostly. It was worried about losing medium. But it wasn't actually "Digital" that was the problem; after all CDs are digital and while they lasted they were the saviors of the music industry. Laser discs were never a problem to the movie studios. What was the problem was computers.
You see: a computer is a completely malleable, rewritable medium. It was paper, vinyl, mag-tape and celluloid and it could be any of them at any given time and you could write over it over and over again. Digital was the removal of information from medium so that it could be rendered on any medium and computers were a medium that could have any information written on them. Computers were like a bound stack of paper that you could have any book written on and then at the flick of a switch have a different book written on the same pages. Computers were TVs that weren't just translating a signal that was flying by at that moment, they were spitting the show out on their own. They were vinyl where the groove was instantly and infinitely recut.
This screwed the music industry because, remember, they didn't sell music; they sold plastic. Now there were these records that could be any record and we called them hard drives. This would be fine if you had to buy one per album, the record industry didn't care about the vinyl as they demonstrated with 8-track, cassettes and CDs. But you didn't have to buy one of these new fangled discs per album, you would only buy one of these discs ever! And the record labels weren't even the ones selling them to you.