having lived as an outsider in other countries, many considered as beacons of public freedom, i found a universal id system in almost all of the cases. there were also some cyclical dependency issues that are hard to break without having one by just getting it done for you by your parents or something. this is where i struggle to understand why in those contexts an id like this is completely acceptable but not for indians?
i do still agree on the front that this is not a bulletproof system, and misuse/abuse still exists. the local tax id (pan) is no longer accepted as valid id because in the past many got it made through non-legit means. but when non-person entities (from pets to deities) are sometimes assigned one in one-off cases, there can be some skepticism on the original goal for the project.
about biometrics, that argument seems weak coming from those who are expats and gave up theirs for their visas. but the one about mandating it to all is something i'd personally thought to stop thinking too much about.