A lot of discussion about caste system in California came up after the Cisco discrimination law-suit by the California civil rights department accusing two supervisors and Cisco of discriminating based on caste.
It's important to note that the civil rights department voluntarily dismissed its case against both the supervisors and court filings show very little evidence to support the discrimination case.
The truth is, there are definitely some folks who discriminate, both here and in India. Growing up as an adult in an small India city (I'd say fairly Urban area), I can't remember an instance where someone asked me what my caste was or discussed about caste until the affirmative action phase came up (in India, the government enables people of certain castes, irrespective of their economic status, by providing them with easier access to top educational institutions, federal and state government employee roles, and sometimes even promotions). Some folks were salty about the fact that one of their fellow classmates got into a better institution/position than themselves despite scoring much less than them. That was pretty much it. (My personal take is that after 75 years of Indian independence and enforcing reservations on the basis of caste, it's time to move on to a criteria that's based on the family's economic status)
Of course, things are different in rural India. We often see instances of discrimination on the basis of caste, sometime with violent endings. And as immigrating to US becomes more and more common, you'll see people from all over India, with different backgrounds, move here. Some are casteist, some are misogynist, and some are racist - just like any other group.
My personal take has always been to stay away from folks who bring up the topic of caste, religion, race or language. That's just me, and I'd say I am slowly becoming the minority.