Were the West Indies productive before the ports and sugar plantations? Was India productive before its railways were built? Something smells of anti-China propaganda in this highly speculative piece.
India had the world's largest GDP under the Mughals and had continued positive growth, but by the end of the British Raj, was facing stagnant population growth and actually reduced agricultural productivity. So contrary to everything you're saying, India was not only productive before the British, it was actually worsened by Britain's exploitation.
Do you have a citation for this? For the entire 300 years of the Mughal Empire? How accurate would that information even have been in say the early part of 16th century?