For the same reason that I, a white English-speaking person, am not going to be able to fool a British old-money old-boys club that I have the same cultural background that they do.

The main benefit of caste comes from 2nd and 3rd degree connections from your family. Simply changing your name won't help you with that.

As far as I know (from some coworkers) they do. But last name is only the first step/flag in identifying to which caste person belongs. Sorry, I don't remember exact details, but there some additional steps like special clothes I think?

Yeah, I think the Brahmins have a vest you can feel on the shoulder, so they do a shoulder grab to act close.

Oh, ffs, that is just ridiculous.

Can't you wear the special clothes without belonging to the specific caste?