This song told the quaint tale of a woman who kept refusing repeated approaches from an unworthy ex, simply by scrawling a terse message across each letter on its arrival.
Technology brings forth myriad shortcuts, as it makes some things impossible.
While stating simply that the message is undeliverable, the implication becomes that the recipient wants nothing to do with you. There is also the idea that modern communication can be more forthcoming, that we should say what we mean rather than appending an ambiguous stamp to an unread message. If you don't want to talk to someone, maybe you should let them know directly. Or just ignore the message and let the silence speak volumes. Most recipients won't bother to determine that the message is bogus, and will not know that you have read the message.