How come nobody accepts an expired government issued ID for anything including identifying you? It's not like we change into someone else after it expires.*
LOL good question. I don’t claim to know the answer but, since that has rarely stopped me from speculating on topics like this, here goes.
Back in the day, you showed your ID artefact - say Drivers License - to a human operator, who had a cursory look at it, and flagged you through.
In today’s digital world, verifying identity is rarely a 100% human decision.
Typically, the human takes your ID artefact, enters some details from it into a computer system (or swipes it in a reader device or scans it under an infrared device), clicks the mouse or taps a button, and, after a second or three, the system gets back with verified / unverified status, which the human must comply with.
(Robust systems do allow manual overrides during system failures and obvious cases of True Negatives, but those are the edge cases).
It’s a best practice to optimize software for storage space, bandwidth, response time, and a few other considerations. As part of that, it’s a standard practice to drop records of artefacts that cross their “use by” date from the database at the backend. Therefore, when you present an expired ID artefact, the system is unable to find the record in the database to verify your artefact against, as a result of which it sends a not verified / failed message to the frontend. Human operators know this and get the futility of attempting to process an expired ID artefact. So they reject it.
That’s why most people won’t accept an expired government ID for verifying identity and other purposes.
PS: When I got to the end of writing this answer, I could think of a few related factors like data retention policies, third party data access, lack of exclusive ID artefact in many jurisdictions, why the artefact used as proxy for ID can’t be valid forever, the Aadhaar government ID in India that does not have an expiration date, and so on. I’ll come back and update this answer when I get a chance.
*: This is the original question I answered. I’m repeating it to help me make sense of my answer in case it’s moved to / merged with some other question that I didn’t answer.