I would described this non named model as the "unimaginative". At a guess I would say that the plan was not involve the design team, use some cheaper leather and rest on our laurels.
That said the "unimaginative" is a practical option today, for this wanting to a basic filofax. It's leather, not the best or tactile, but durable. The rings can be changed if required as they are usually not riveted. Best of all these can be picked up for less than £20.
So if your looking for something not new or sparkly, let's say understated the "unimaginative" could be an ideal choice.