Earlier quoted context omitted.
> Possibly a security measure? What I read in the article sounded like the ID was required to submit an entry to the contest, not to be present in the area. I would need more information to comment on alternate reasons. > You can't authenticate without Aadhaar OTP. And don't expect the government to send OTP to an unverified mobile number. Authenticate what? Last time I needed a prepaid SIM card (in the US), I bought…
prepaid SIM card (in the US), I bought it on eBay This is highly unusual now. For instance most countries in Europe will now need to see your passport to enable a SIM card. So India isn't an outlier. The stated reason, I believe, is terrorism. Whether this is Orwellian I leave for you to decide.
What it does enable is surveilling a person's location and some of their communication without having to do something requiring resources and the possibility of alerting the person that they're a target.
For the record, it's not unusual to be able to buy and use a prepaid SIM card anonymously in the US. There have been a couple proposals to ban it, but they came nowhere near passing.