Exactly, abstraction has consequences too: explosion of classes, packages, modules, libraries, thus hierarchy, wiring, dependencies, lost versioning trace when moving around things etc. The author assumed we are now saved from hassle by introducing new abstraction in some naive example. That is not so easy.
The example was a real-world example I encountered the morning that I wrote the article. The article is 1500 words, I'd love to do a 5000 word version sometime with more in depth examples.
As for explosion of things, there's accidental complexity and necessary complexity. Complicated things are going to have complexity somewhere. The question is where to do put.
The article is arguing for balanced, carefully groomed tree of objects. In other comments I clarify I'm talking about attributes not methods or APIs. Flat APIs can be wonderful. Attributes are different story, since they are global variables that complicate every single method in the object past and future.
