This is ridiculous
I'm curious, why do you think it's ridiculous?
Enormous waste of time.
Enormous. By the time it takes that person to carve out and colour in their cardboard iPhone, you could have a working prototype in Invision that you can put on a real device in front of someone.
But it looks so pretty and creative in my blog post!!!1!
I was nodding my head agreeing that maybe the time had passed for paper prototyping. Then I remembered that at my new job I didn't have access to invision, or marvel, or even keynote. So maybe some people are more limited in the tools that they have available. In the end, anything that works is still good if that is all you have. Any testing is better than no testing.
FWIW, I feel like the title would be more reflective of the article if it were repositioned as a statement, not a question: "What UX prototyping is and why you should test at this stage."