Highly religious societies have a strong desire for tradition, and tradition is "women don't work and have no power, corruption is rampant, new things are bad (because they destroy the golden geese that keep the upper class rich and in power)". Pakistan and India are going nowhere soon.
So, yes, you're right, it's China. At a rough pulling-numbers-out-of-a-hat, China will be back in sync with the rest of the world average (for levels of religious activity) somewhere around 2050, when it will be mostly Christian and Buddhist.
"They need only 1 or 2 more generations to truly rival or even surpass China."
These two seem to be in contrast. Do you know what is being done to change education for most people that would radically improve outcomes within 1 generation or 2?
The state of education is appalling. And yet at the same time, you see tons of those in the low 90% of the population checking out Facebook in their cheap phones with 4G connectivity.
Either way, my outlook for India is very positive. IMO They need only 1 or 2 more generations to truly rival or even surpass China.