I’m not sure what workflow to choose - old one with “baked” textures and etc or just create a set of basic materials and then use pass them around via material attributes.
Material attribues way is more costly or less or it’s simply another “interface” for creating materials?
You are forgetting material instances. The discussion is to be between that and layers.
And then it is about equal, it really comes down to what you prefer IMO. I use a mix of all three (third being unique normal materials) dependent on what I am doing/what others did.