Work 40 weeks and the production is 120 articles a year. Not a fortune, but a nice supplemental income for a retiree. Of course, this is harder work with tighter deadlines and involves marketing effort. Indeed, the tax benefits alone might make it worthwhile. See your accountant to determine how this small business could help your tax situation.
Most people think they can sit down at the computer and write salable copy.
This may be true for some, but for most, they need to learn the types of copy that not only sell best but are the easiest to create. For example, travel articles are nearly impossible to sell. There are specific ways to market writing. Join a writing club to get in touch with other writers and learn about the various markets. A trip to the library or bookstore should provide ample reference material to help get you started.