As I recently pointed out, even though mass storage is pretty inexpensive, there is also the consideration of time and effort spent with backups and validation and such that goes along with the whole thing. I think that data architects need to include in their efforts ways to summarize and archive data even offline such that it can be retrieved effectively IF AND WHEN needed to get to the detail.
Massive storage of detail may be of value in the case of audits and such requirements, but is hardly of much value as it ages and can be more meaningful for many needs if well summarized.
Offline storage of detail can be so much more cost-effective if it is properly designed and managed.
One of the best days of my IT career was the day I told my boss if the problem was so simple he should go fix it himself.