I am not sure why anything today made from cardboard has to become a hit. Probably people just like to see when something is recreated and made from an unusual material like cardboard.
When I was a kid I was reading some books about photography and there was a tutorial on how to create an usable camera from cardboard. This article reminded me on that days.
Kiel Johnson is an American artist who has created an interesting collection of cameras made from cardboard. Those are full-equipped cameras with all lenses and similar parts. and they can be used for taking some quality photos. Also, there you can see some old models of cameras like polaroids or even older ones.