"..the implication is that the rest of the world is and always was poor."

Wow.  

I guess all those stories told of fantastically rich foreign rulers, and factual tales of the riches of the those rulers brought back by explorers and merchants were completely ignored.  Of course, that might be why those merchants kept going back to India and China, etc... stupid merchants going to trade with historically poor people!  What were they thinking! (/<sarc off>)  I imagine the decision to colonize / conquer India was also based on such thinking?  I am guessing you would argue the opposite, as would I.