At no time did I say that the majority of Indians speak English. I said they have the largest English-speaking population in the world.
Assuming that 300 million Americans speak English (to be generous), that would require more than 22.2% of India to speak English.
According to the last census, conducted in 2011[0], India has about 125 million English speakers. That same link says this is "projected to quadruple in the next decade".
If that supposition is at all accurate, India now has the largest population of English speakers in the world. The next census is in 2021, so we should know for sure by then.
India is a populous country with English as an official language. If you think all its inhabitants speak English you're in for a surprise should you ever go there. People are educated in English, certainly; however Canadians' well-known mastery of French as well as Irish people's mastery of Irish shows this criterion doesn't necessarily amount to much.
I'm wasn't disappointed by all the other technicalities in your post though, keep it up