You must have been lucky enough to be working with Indians who were all from the same caste. I've worked as an intermediary to different teams comprised of competing castes because they refused to work with each other.
Since you appear to be posting from a throwaway, care to share which company this was at? Having worked with plenty of Indians (and being Indian myself) I don't recall caste ever being a factor in anything at any company I've ever worked at. I'm not so closed-minded as to say it's impossible but it would be useful to get more information and context. At the very least so we know which companies have toxic cultures like this.
My experiences and jobs have all dealt with working in small teams; 4 to 8 people from project mangers, designers and developers.
It's easy to get lucky with small numbers. I was a researcher and I worked alongside teams of hundreds of people, mostly Indians. I was a mentor to a bright young hard working "untouchable" who showed lots of promise. He informed me about the caste system and who was in what caste. Sadly once I left the company the other teams who would work with me ended up shunning him and driving him out of the company. I got him a job at Facebook and he's happy there so at least that worked out.