Actually, my generalization (and yes, like almost all generalizations there will be edge cases) may hold true, thought not quite yet, which is why I didn't slam the door shut unequivocally. It is interesting to me that my comment triggered such emotional responses in a few people here. While being a little trollish, I really wanted to see where a lot of people would run with my admittedly obtuse statement.
To many people Moore's Law is an unalterable universal truth but many of the current projections have it falling apart soon, if it hasn't been dis-proven already. I feel the same way about the hard drive issue. In general, the majority of computer users today are not saddled with a need that demands steadily larger and larger storage mediums. People who compress large movie libraries to a single hard drive or store vast amounts of astronomical or scientific data are not the norm. With the advent of cloud computing and increasing bandwidth across the states, I just feel that eventually client-side data may even go into decline for the majority of users. There are a lot of maintenance and risk associated with storing everything locally without good fail-safes or a clear backup plan that cloud-based services will eventually offload from many users as well.
Certainly, this is a long-term theory that will be played out over the next ten years or more, but to say that we will continue to expand the need for hard drive space infinitely seems to be more obtuse (at least to me) than even my original provocative thought.