> Existing financial system is perhaps suboptimal in terms of transferring money, but it has pretty good tools of ensuring the expected goods and services flow back

In what way is physical money different from bitcoint in this aspect? Is there an implied statement here than for all the ages where we did not have electronic banking, money was inherently insecure and built on crumbling bride pillars?

Treat bitcoin like physical money, and most issues goes away. I don't post thousands of money to a strange in a different country to hold them for me, nor do I give physical money to a store before I have the product in my hand.