Actually, due to the huge amount of affirmative action, upper cast people often try to be identified as lower cast.
In India 50% of all university seats, government jobs, and other opportunities are reserved from people identified to be from the under-privileged castes. The lower castes are also one of the strongest political blocks with huge electoral powers.
If anything the lower caste people want it to be easier to prove they are in fact lower class so they can get all the benefits there in.
The social stigma exists, but is not dependent on or impacted by the government. Its going to remain till a few generations of Indians have lived and ancient truths on this matter have ceased to be the standard.