Clay Shirky, in his Here Comes Everybody, devotes a chapter, "Everyone is a media outlet", to a comparison of the decline of scribal production to the decline of "professional" journalism. He sets up this analogy on faulty legs that leave the argument that "what was once a chasm is now a mere slope [between "professional" journalism and committing acts of journalism or journalistic-like writing or photopublication]" completely unsupported.
The problem is that the scribe's production of books, which was, for the most part, merely rote copying (with mistakes sometimes adding very interesting flavor to the resulting books), is not analogous to the acts of research and authorship that a journalist does. And I don't mean a "professional" journalist, just the act of researching and writing a thorough report of an event or events.
Clay mixes in photojournalism and stock photography, two very different functions in the scheme of things, as one is concerned with immediacy and the other with illustration of events with handy and cheap symbolic images, to make his point that it is in organizing data that most value is created:
"Who is a professional photographer? Like 'journalist,' that category seems at first to be coherent and internally cohesive, but it turns out to be tied to scarcity as well..... Much of the price for professional stock photos came from the difficulty of finding the right photo rather than from the difference in quality between photos...."
Photojournalism was and still is expensive, because someone has to take the bet that they can be in the right place at the right time. As a result, one photo can be worth months' or, even, a year's pay, because it took a year to be in the right place. Likewise, the reason stock photos exist is that they have been composed in the past from false realities (models posed in "natural" settings) or captured during the long effort to make a valuable image, and were ready for the future need as a result. In both cases, production rather than distribution is the essential cost.
Widespread amateurization doesn't make it cheaper to produce a staged photo, it simply increases the likelihood that you can find a "real" image of something at a lower cost than the composed image of the photojournalist or stock photographer.
Shirky also cites the music and film industry, which engages in "distributing music and moving images" that is being undermined because "laypeople can now move move music and video easily." Without getting into the distinctions between artists who can produce themselves and those that need packaging by a marketer before their music doesn't suck too much for human consumption, the real value in these industries is production, not just distribution. Try to make The Lord of the Rings trilogy on less than $500,000 and you will see what I mean. Production includes the financing of risk, too.
Additionally, Clay dwells on "professionalism" as the essence of journalism. I'd like to see his take on the evolution of journalism, which is characterized by amateur writers becoming paid writers as they try to fill their own or a friend's press with content. Over the long run, most great journalists never had a journalism degree. Professionalism actually rose with the proliferation of media outlets as a way of credentialing people, mostly to the detriment of the dedication to reporting the perceived truth that drove the rise of mass journalism.
In many ways, Shirky treats anything flowing over a network as an undifferentiated mass of content on which his economic and social rules operate.
"The entire basis on which scribes earned their keep vanished not when reading and writing vanished but when reading and writing became ubiquitous," Clay writes. Indeed, it is so, but that is also when those scribes began to write their own works, as he points out with regard the Abbot of Sponheim's 1492 defense of the scribal life, which he chose to print and distribute through movable type. Rather than a chaos during that 100 to 150 year period when scribes and printing presses competed with one another, there was a long process of change that was largely comprehensible to everyone involved. For an excellent history of this period, see Elizabeth Eisenstein's The Printing Press as an Agent of Social Change.
What changed for the scribes was that the church would no longer pay for their work, because it no longer had a monopoly on readers, so they had to evolve different skills or, rather, focus on improving existing skills for the new channels of distribution. In other words, they had to become authors.
Scribes were copyists whose errors did introduce some of the most interesting elements of the books they reproduced (and, so, were failing as "copyists"). At best, they were masterful annotators and commentators on those works that passed beneath their quills, but not authors in the modern sense. Both authoring and annotation/commentary survived and thrived because of the enlarged markets for printed work. The scribes didn't die off, they evolved into, among other things, academics, scientists and historians.