Right. In an ideal world you'd be using a bunch of CC content in a presentation, the appropriate IPTC fields would be filled in, and you could press a button and a block of credit text would be generated. (That's primarily about CC-BY I realize.) In practice, it's an incredibly manual process that I'm guessing most people don't follow and, even for those who try to, it probably breaks down more often than not.

Then there are all the issues with the NC and ND license variants and what they even mean exactly. But that's another rant.

EDIT: I'd just add that clearing rights and giving credits have been an issue for ever. On more than one occasion, I've gotten a semi-panicky email (and I think once actually a phonecall in pre-email days) securing permission to use one of my photos that was clearly on the verge of going into production. Presumably, someone came along and asked "You do have rights to this, correct?"