Social Security Numbers were never intended to be used the way they are. They were expressly for identifying you to the Feds for the purpose of SSI. Business just looked at that and said "hey, that's a good way to identify people" and ignored the feds when they asked politely for them to fucking not.

I mean, this is where a biometric identity authentication system would be beneficial, but like fucking hell if I trust any current entity, government or private, to run it securely for anyone's benefit and not sell the data to 3rd parties or keep it secure.

eIDs are coming. Be careful what you wish for.