We really wish they were dyable, too. This skin is not dyable because of how materials work in our game - it would be a huge lift of redoing how a ton of materials work (not just on this armour) on the tech side in order to make the glowy bits dyable. Because of that, we kept it as one colour for all.
Because the glowy bits can only be 1 set colour we redid the armour itself to match the purple in the marketing art so that people hyped about the art aren't disappointed in the colour itself once they get in-game.