First of all, that poll is about discrimination against Indian-Americans (presumably based on race or ethnicity), while TFA is about caste-based discrimination.
Secondly, the option below "major problem" in that poll is "minor problem", there is no in-between. In other words, 90% or Indian-Americans think it isn't a major problem, but over half do think there is a problem.
Most importantly, polling opinions about this is the worst method of determining if discrimination exists. A better method would look at objective measures like salary/job/hiring rate/layoff rate/etc of lower-caste Indians compared to Indians as a whole.