“India and Russia are 3rd largest and 4th largest economies in the world.”
India, Russia, and China are likely TWICE the size of the US and Europe, at this point (with Europe sinking fast).
We should compare economy size based on PURCHASING POWER INDEX, not currency exchange rate.
For example when bigMac is sold in USA it adds $6 to GDP. Same bigMac is sold in India for $2 id adds only $2 to India’s GDP.
In reality the GDP increase should be parity.