the comic says “be young and shut up” which translates to “sois jeune et tais toi” in french which was a slogan of the “pink rebellion” which was the paris riots that the movie the dreamers is based around, it was riots that took place when art students and the youth in general of paris used art to rebel against the government when they felt like they weren’t being heard. There were movies, music, books etc.
in the comic it says “firstly we must reclaim our identity and repossess our control of it. it’s simple, you could almost say its black and white. Until then there won’t me any pop music or dancing with long hair” this explains the social media disappearance because theres obviously going to be a change in image, At the end of the chocolate music video it says “poetry is in the streets in full living colour” in french “la poésie est dans la rue” also featured in the robbers video, mattys shirt etc, so they’re obviously returning in colour as opposed to their old black and white aesthetic, hence again the use of pink which represents rebellion - pink auras are often around those people of creative nature. It’s the start of the revolution.