Most people can put words together into sentences. They can communicate adequately without being great writers. Most programmers can write some kind of program. It probably won't be very good, but most companies don't really need it to be very good. Most companies only need basic programming skills. A college degree in computer "science" from anywhere is good enough, and the job is just a job. It doesn't require much in the way of continuing education, conferences, workshops, or someone who is so interested in the craft of programming that they are always trying to learn more.

Such people can write, but it's just basic writing. They are not essayists or novelists -- and keep in mind that there are lots of articles and novels that get published that are not particularly well-written or worth reading. Obviously such things seem to sell well enough to make the effort and risk worthwhile all around.

But someone who dedicates themselves to writing, who goes through the struggle of figuring it all out and discovering their own place in the world -- this is a very different kind of writer (of prose or programs) than the average programmer. This person can produce more functionality faster, and the results will be clearer and deeper than ordinary code.