Because those are credentials of last resort trusted at scale. Losing who you are is much more challenging than a secure hardware token or a soft crypto primitive. If you lose a gov credential, the government itself does the hard part of identity proofing to reissue a credential for consumption by those who require identity assurance to complete a transaction or action. A business or other party can then trust that credential, reducing the risk of loss through identity fraud.

Optional of course. For those who want to ride the lightning, they should be able to opt out and eat the loss if they so choose (assuming loss of authentication mechanisms, whether that be passwords, passkeys, private key(s), hardware tokens, totp seeds, etc). For the rest of us, “here is my driver’s license, state ID, or passport, please unlock my property or I’m engaging state and federal regulators and the legal system.” To do otherwise is in violation of consumer and citizen property rights.