should GPT be putting a signature into any text it produces, a kind of watermark or attestation? it could be even embedded in the characters themselves. Obvious

should GPT be putting a signature into any text it produces, a kind of watermark or attestation? it could be even embedded in the characters themselves. Obviously not foolproof as you can simply remove it but for those who forget it would be an instant tell that some or all of a text came from AI. conversely human authors could put an attestation of human origin into any text. then text missing the attestation becomes suspect.