Trade mark law is the only one which has to be protected or they can lose the right.
It makes sense to me what gw are doing. (I'm an IP specialist).
Trade mark = protects brands or "badges of origin"
Copyright = protects artistic work. Copyright protects the expression, not the idea though. Which is a whole thing in and of itself.
Patents = inventions
Designs = shape of products. Usually the shape of like a chair or phone etc. There is an overlap with copyright here. But designs usually are required when things are industrially applied (mass made). But judges will bend copyright often to cover this.
Plant breeders rights = plant varieties