This is my speculation:
The problem is that there at least 4 databases that track your citizenship status and none are the single source of truth (which is a major design flaw but that’s the situation).
* USCIS has 2 databases: SAVE and database of aliens who have obtained benefits from USCIS. State DMVs and social security work with SAVE. SAVE has more entries than the alien benefits days are because people born in the USA or who have CRBAs normally would not be in the alien benefits database.
* SSA keeps a database
* The State department keeps a database
It appears the SAVE database requires both USCIS and SSA to confirm updates. Makes sense since most U.S. citizens have birth certificates
Consequences:
1. If you claim to be a U.S. citizen on I-9 and your employer uses e-verify, e-verify might fail and eventually you might be terminated.
2. If you claim to be a U.S. citizen when applying for a drivers license or state ID, SAVE might fail and your document might be delayed or denied. Some states will accept an original naturalization certificate in this situation and some of those states won’t accept a passport or passport card.
3. if you apply for social security benefits, a discrepancy between your claimed status and what SSA thinks your status is could delay benefits, especially if you plan to live outside the U.S.
4. This is no speculation: If you need to replace your social security card, in most states U.S. citizens can do this online. For the part 3 years when SSA closed field operations, that was nice option for people who had all their documents stolen.