These myths have been thoroughly punctured by now. Angus Madison's research on historical development is stellar about this:
http://www.ggdc.net/maddison/oriindex.htm
The difference between Indian, Chinese and European technology was real, and it existed long before 1820 (Victoria's start).
Of course the fact that Europeans began developing a global trade apparatus didn't give them, all by itself, the ability to dominate the world. But the fact that China opted out of these innovations set it on the path to stagnation. The bureaucracy that dominated China had some competitive advantages:
Not everything about Ming's development was bad, it was extraordinarily good at population growth. It had to be given how extremely labor intensive Chinese agriculture was. But the priorities of the Han Ming/Qing bureaucracy were self-interested in stability, which lead them to be resistant to change:
Relative technological stagnation was a characteristic of 17th century India as well. It is somewhat insulting to Indians to refer to the entire subcontinent subjugated by the British by 1819 as "weak and disorderly". They did however have the same kind of trouble the Chinese did replicating European advances:
All of this is very unhelpful for player of an Indian or Chinese Tech nation in EU4. And the relative historical development of China vs Western Europe bears this out:
Truly no one rational would dispute that the West's relative development skyrocketed after 1820, but this should not blind anyone to the western advances in development before 1820 which made that possible. The catalyst being the global trade network that China and Japan neglected:
By far the most repeated myth I encounter on the EU4 forums is how China and India retained technological parity with Western Europe long after they started to fall behind.