The author's examples are not relevant to the argument. If you're just trying to design something that is, on its face, beautiful, there are obviously many viable styles besides modernism. The goal of web design is different from the goal of palace design or ornate ceiling design. Web design must be usable or it has failed. I think a better analogy in the physical world would be the design of tools. If you were driving nails all day, would you rather use a modernist hammer or a hammer that looks like that Rococo table?

I take his point that modernism has become close to dogma for some web designers, but I don't see how an abbey built in the early 1700s relates to a website.