Yes, in the eyes of future generations, tools like pliers and wrenches that seem insignificant actually needed to be custom-made during this era.
Not only were they expensive, but if a craftsman wanted tools that suited them well, they might have to work alongside the blacksmith for ten days or so.
As for why blacksmith shops didn't produce them in batches?
Every craftsman's habits were different, and most mass-produced tools wouldn't sell.
Take the simplest wrench, for example. In most countries, each company used its own screw specifications. What size opening would you make for a wrench? And some screws have hex heads, while others have triangular heads, making them completely non-interchangeable.
So craftsmen could only customize, handing over wrench blueprints to the blacksmith who would start working.
Historically, the United States had copied many British machines, but due to a lack of complementary tools, many of them could not be utilized even if they were built.
