Ye not the pipe, go check the button that the blue player stands on in stage 1
Viewing post in Flo Hider jam comments
So like @SkinnyP12 said, we wanted the buttons to match the pipe it turns on/off rather than the player's colour, so that's why the button on L1 is green, because it turns off the green pipe.
We actually did have a discussion about the colour of the button (green vs blue), and we could just as well have gone for blue, the gameplay would stay the same though.