But they're not semantically rich. People who speak the code aren't doing it to more efficiently communicate, such that a long and complicated message can be expressed quickly. They are taking a short simple message, stripping away all the details, then padding it such that it becomes more verbose and vapid. This makes the real message harder to decipher for the uninitiated, it removes information even for those who understand the code, and it serves as a display for people who appreciate the flourish. There may still be some meaning left, but it's semantically emptier.

Further much of it is not even code. Examples like the microsoft letter are clearly a performative act to soften the blow of bad news. No one in the know is reading such an email to discern some hidden message; it's written to not be read.