Except if Toyota's business is worth the cost of keeping 2-6 months of product in the warehouse, it isn't really like an "unneeded resource" that the JIT approa

Except if Toyota's business is worth the cost of keeping 2-6 months of product in the warehouse, it isn't really like an "unneeded resource" that the JIT approach would want to avoid. They are being paid (in a sense) to hold those parts, so it is not wasted.