Quick Question: Subframe connectors- WHY didn't they do this from the factory?

Any mass produced car was and is assembled as quickly as possible in the era in which it was built. The purpose of mass production is only one. To make money. It's not to build quality. You want quality? Look at Rolls Royce. Everything built by hand. Everything the same. That is true pride in workmanship. Of course the price reflects it.