I think the author might be making the common assumption that other people hold the same preferences they do. In the footnotes they speculate that most people prefer decorated objects but buy plain ones "to appear normal". Is it really so bizzare to suggest that many people actually prefer the clean, simple aesthetic?

One example shows some patterned plates. If you told me I could buy those patterned plates for $1, and the same plate but perfectly white for $10, and no-one but me would ever see or use them, I would take the $10 plates every time. I find the patterns annoying and distracting, especially for a surface which I want to ensure is clean.

On the streetlight example, I think the difference there is less a change in aesthetic and more a change in cultural expectations around public works. If you built the ornate street lamps today, even if it was in style, it would likely be decried as "unnessecary spending".

I do think there's a reasonable point to make that in today's market of mass-production, any preference besides the single most mainstream, mass appeal one is extremely hard to find. I wish the author could find more options that suit their preferences, even if I personally don't share them.