Paid writers

Does the existence and widespread availability of the web mean the end of professional, ie paid, writers? Stephen Downes thinks so. He asserts:

"It's a funny thing, how often I read articles that say, in one breath, that internet technology is one of those that "changes everything" and in the next breath talks about how people will still be paid for writing. You know, if everybody's doing it, people aren't going to be paid for it any more. Take reading - it used to be, kings and lords hired scribes not merely to write but to read their correspondence. And of course the average person would depend on a monk or a priest to read the Bible for them, much less any more mundane communication. Try getting yourself hired as a reader today! And imagine the laughter you would face if you boldly asserted that you would no longer share your reading unless people paid you money!"

I believe he is wrong, both about reading and writing.

Reading

Over 5 million people in Britain can't read or write today (see this video although, as one of the commenters says, the teacher in the video uses 'laying' when he should have used 'lying', which is rather unfortunate given the subject matter, but still). Presumably many of them have to have people read stuff to them, and possibly even pay for that service.
We do have paid readers, and we call them 'actors', 'poets' and 'news readers'. As Geoff Martin says in a comment on Downes' blog, "… even today we get professional readers - take the narrators of audio books, or the people who read the news."
When I have managed teams, I have often asked a member of the team to read a report to me and then let me have a summary of it and suggested actions. It's not that I can't read myself, but that it was a better use of resources to ask someone else to read it for me, thereby in effect paying them to read for me.
As a person who has some understanding of business and publishing in particular, but who is not a legal expert, I never sign a contract without having an expert read it over for me and then give me their opinion. As a member of the UK's Society of Authors and Federation of Small Business I pay subscriptions, partly in order to avail myself of this service.

Writing

Similar arguments apply to writing, where too we find the themes of necessity, convenience and expertise, and an economic argument.

The people who can't read or write need someone to write letters and fill out forms on their behalf. They may not always pay for the service, or pay directly, but the need for such a service is there.
It's true that anyone can write about anything. However, if you want something to be written by someone who actually knows what they're talking about, you may well want to find an expert in that field and pay them.
If you want something to be written well, again, you may need to pay someone. There are loads of people who think they can write, but who are actually pretty bad at it. Don't believe me, or think that's my ego talking? Have a look at Angela Hoy's collection of 'worst book proposals' .

I have an interesting example to share from my own experience. A couple of years ago someone commissioned me to write an educational ICT strategy for a Local Authority. One day, I was in a meeting with him, and was astonished at the ease with which he could reel off figures -- accurately -- without reference to any notes. When I told him that afterwards, this is the conversation which ensued:

Client: Well, everyone has different strengths. For example, I couldn't do what you've done, and write an ICT strategy.

Me: Of course you could. All I did was write down what we both know about.

Client: No, I'd sit there staring at the blank sheet of paper, not knowing where to begin.

What was going on there was what is known in economics circles as the Law of Absolute Advantage. I was (perceived to be) better at writing than the client, and he was better at remembering figures than I was, so it made perfect sense for him to concentrate on the numbers while I focused on the writing.
But what if he had been better than me at both skills? That's where another 'law' of economics comes in, the Law of Comparative Advantage. In a nutshell, although the client may have been better at both skills than me, if he was comparatively better at the number skills than the writing skills, it would still have made sense for him to pay me to do the writing.

For all these reasons, I don't think that people whose earnings derive from writing need worry too much about paid writing opportunities disappearing any time soon.