the longer those decals sit on the paint, the more it will fade around it and if you remove them they'll cast a shadow in that area.I wonder if the matte paint is going to cause any issues removing the decals. Any sort of imperfection left behind is going to be a pain in the ass to fix.
I personally think the stickers are rad and I'd keep them on there. But I would at a minimum ceramic coat the car in a matte ceramic product for UV protection.