It's an animation that some nobody (in the animation industry) wanted to write and get exposure for. It's an animation that gets viewers exposed to Madeon's name.
Wrong on both accounts. Porter Robinson (not Madeon) was approached by Crunchyroll and asked if he was interested in writing a story for an original animation with a Japanese studio. Yes, he is a mainstream EDM artist but he is an animation fan just like you and I. He then proceeded to lock himself up and wrote the story to Shelter in 3 days and during the course of a year, traveled to Japan several times to work with A-1 Pictures on the development of the short.
Also as an EDM fan myself, the moment any small artist collaborates with a mainstream one, they have made it big and don't need any other exposure and Madeon was already fairly popular to begin with.