Quite right. Content disposition paramaters are supposed to carry
generally
meaningful information that may be needed to act on the associated
disposition.
So we have filename, creation date, and modification date parameters,
which are
all useful when putting message content in a file, which is what the
attachment disposition often ends up doing.
Creator/author identity only kinda sorta falls into this category; IMO
version and copyright information miss it by a mile.
The above and Keith's comments w.r.t. copyright notwithstanding, what
about
some indication by the author to indicate a preference against
long-term
archiving of the media content?
seems reasonable at least from a theoretical perspective. from a
practical perspective, I wonder if it's at all realistic to request
that email not be archived, or that some part of a message not be
archived.