I think you're side stepping the point of the article which wasn't that he was arguing for complexity in design but that the general public has a tendency to "worship false images" as Don would put it. That is the impulse when comparing two products side by side in a department store setting is to go with the one with more knobbies and twiddlies. Sure there may be one with simpler interface but the purchaser may equate that to "less capable".

It's all related to marketing.

A way that sellers of products that do have simpler interfaces get around this is either with lots of literature or very thorough product demos. People here may want to use the Apple brand as counter examples but that's wrong. Instead of complexity in the design of the product the complexity is in use. Demonstrated with lavish expos and advertisements. They're still selling you on capability.

But not every product manufacturer has accessibility to that kind of marketing prowess. The best you can hope for your widget in the department store is built into your product. And that means the product has to sell itself. In that case, as a designer for that widget, it would be good to know that simplicity is overrated.

- By the way. You should really pick up "The Design of Everyday Things" by Don.