First, you should set up a lightning wallet. I tried to zap you but couldn’t. 

I see a loose correlation between lack of empathy and the increase in adoption of money as a technology. 

I think we currently have more empathy for each other than at any point in history. The ages you refer to were dangerous and while you would trust your village you would strongly distrust anyone outside of your circle. 

There definately was a much higher need for trust pre currency and this was a highly limiting factor in the growth of civilisation. 

A human can only really manage 100 or so genuine relationships. 

So if trust is a requirement for trade then the maximum size of your settlement is limited by that. 

Money does remove trust from the equation. That’s the point. 

It also solves the coincidence of wants which was another limiting factor. 

Because of money we can travel globally across cultures without the need to trust which paradoxically allows us to be more trusting.