The effect of Military budget cuts

When you don't upgrade all your units in Civilization

Wouldn't that actually be more expensive? Considering that somebody has to spend hundreds of hours chain linking the mail? As well as the cost of the material? Body armor and helmets can be mass produced. Though I would asume the guns and gadgets to cost more than the sword. I may be totally wrong, or totally right. Welcome to the internet :P Somebody is bound to correct me if I am wrong.