These people were given refuge, every facility and liberty to progress, and yet retain their cultural and religious identity. Even after centuries, the religious luster of these groups has not waned by an iota. Insecurity of numbers thus can hardly be a justification for conversion to Christianity or Islam as the presence of these faiths is not insignificant. The intention to convert cannot also be to impart ultimate and superior esoteric knowledge since the spiritual pedestal of eastern religions has long been widely held to be much higher than that of the exclusive faiths. Every man has his own equation with God and has to evolve his own path to Him.
Salvation is essentially a personal matter.
There is no collective road to salvation, just as clothes stitched to identical measurements cannot fit everybody. Where there is organization there is little chance of individuality and hence no salvation. Exclusive religions in general and Christianity in particular are the most organized religions. Hence people from the West, who are seriously in search of the truth come to the East, particularly to India, to seek guidance from Hindu gurus. If we see the condition of the people who were forced to convert to Christianity and Islam in Africa and South America, we see that their condition, material or spiritual, hasn't turned for the better.