"Bias for default" - can you explain what you mean by this? Doesn't everybody have this bias? (i.e the countries where organ donation as default option on DMV forms have the highest organ donors percentage)
You can but that might not yield the result, Because the surname isn't associated with his caste, It is his father's name which is "Pichai Sundararajan", Yes he got his grandfather's name, In tamil (which is his mother tounge) the word for Grandson is "Peyaran", it roughly translates in english to "Namer".
Unlike the commenter 'dmod' above, I am from the same state as sundar pichai, So i can sort of figure out his caste, But never bothered to conform. Because as 'dmode' says interest in caste is not really something that is prevelant among yonger indians.
But as i am getting older i am interested in caste, But that is more like old people getting curious about their ancestory and going to 23Andme.