Besides that, sometimes multiple entities do need to know who you are; how is it supposed to work if your insurer and your healthcare providers don't aren't able to match you up to one person?
It is possible to make things sufficiently mixed up that the entire consent-absent aggregation system falls apart. Prohibiting them from using social security numbers and otherwise not providing any alternative unique primary key would go a long way toward that end.
> Besides that, sometimes multiple entities do need to know who you are; how is it supposed to work if your insurer and your healthcare providers don't aren't able to match you up to one person?
You don't need a single global identifier for that. You can give your healthcare provider your insurance policy number.
Not really. Log onto Spokeo, look yourself up, and see how many errors there are -- but at the same time, how the data is "close enough" to be useful. All compiled without a single identifier like SSNs.
Centralized identification is bad. There exists no competent, accountable, trustworthy party to administer it. It inherently gets abused to aggregate information about people that should be private. Monolithic systems are slow to adapt, allowing attackers to continuously outflank them.
When a bank needs to identify you, let them use your bank account number. When a doctor needs to identify you, let them use your patient ID number. And never the two shall meet.