As an American/Swedish dual citizen…

I think I’ve only had to show mail to prove my address when first getting a driver license in a new state. So that’s a thing yes, but not very common.

Unlike in Sweden, in the US you don’t register/update your address with the authorities when you move. It’s not that the US doesn’t have a “working database” for that – it’s just not a thing at all, there’s no population register like in Sweden.

In Sweden you use your personnummer for identification, but you also have secure authentication methods like BankID that aren’t available in the US. Your personnummer is public information and you’ll provide it just about everywhere because there’s little risk to you.

In the US we use our social security numbers for both identification and authentication. Because they’re used for authentication, they’re considered secret and we’ll only share them when strictly required for necessary services (like government agencies and banks). This is obviously really poor security and they weren’t originally intended to be used for authentication, but it is what it is.

Swedish system is of course more efficient and more secure.