Two comments.

As the company librarian, I can edit the official copy of OldeCruft.pm, but I don't know how many thousands of old private scripts may be depending on it. So I wanted to be able to add one line to OldeCruft.pm and thus all other scripts would start carping automatically. I can't just email the developers to say "add this weird -Mdeprecated thing..."

I want deprecated to be agnostic; it doesn't care who uses it, it doesn't know which modules are deprecated. By including this pragma, you mark the module as deprecated, and that's all you need to know. Modules come and modules go, and I'm not interested in editing some custom and touchy intelligence in the 'deprecated' module every month.