Spacer GIFs which are resized for narrow screens (300-750px) using CSS depending on the tag's width attribute. That's not a technique I've seen before:

> img[src='s.gif'][width='40'] {width: 12px;}

(from https://news.ycombinator.com/news.css)

I don't understand why anyone would consider this sad.

Because it's not really reliable and breaks in many situations. reddits old nested divs work much better in contrast, and have a layout that matches the semantic situation better.