it did take several centuries to create a framework for economic cooperation that works for large geographic areas and that was not based on the classical Gree

it did take several centuries to create a framework for economic cooperation that works for large geographic areas and that was not based on the classical Greek regime of slavery (that might work as a summary). For an individual of low birth serfdom seems preferable to slavery, however it must be more difficult to organise a 'big' economy on top of that The western Roman empire needed grain from North Africa and the Middle East - it needed ships to transport all that and would pay with silver from Spanish mines - you need a slave regime to maintain all that. A system with more independent actors that achieves the same level of trade / cultural exchange is inherently more complex (needs more complex system of laws, finances, everything) , but is in turn more scalable. I think Europe 'won' because it was a distributed system. A country/ruler can go bad, but as a whole connected by trade and cultural ties it kept going further (each ruler had to keep up if not to be swallowed by the neighbours) . However big unified realms like China or Russia all rise and fall as one entity - and it takes longer to recover from a big crisis.