Not ITD but reporting is done by banks and it is a standard process these days. If PAN is there it gets auto-reported. People open account using eKYC where PAN and Aadhaar gets linked at first step. Without PAN or Form 60, it is not reported anywhere. Like my father post office savings account didn't had PAN for 25 years and only last year he updated in reKYC as having PLI insurance maturity amount coming. This year same Postal savings acocunt interest is updated. I wasn't even aware of this account. So kind of missed addition of meagre interest reporting in ITR for so many years.
Just like banks reports TD interest in 26AS if tax is deducted, same way systems are connected to AIS and every bank send whole file to ITD with PAN data.
Sir, don't just take the Rs.2 case. Because of this reporting they are getting lakhs to crores in tax also which people used to hide before. Even I started reporting savings account interest after Arun Jaitely made it compulsory before that, I many times missed to report. But as it used to be less than 10K, so deduction was there in 80TTA which would have not affected tax liability.
There is also a benefit of AIS. Some people forget their accounts and PAN/Account reporting made them get to know that they have so and so account running since AIS started in 2020. Usually these people used account once a year and then forgot. Even if it becomes dormant one can easily get old ais data to know.