The problem is that if we modernized most of our iconography, a heck of a lot of things won't be able to be represented simply with something distinctive enough. This is largely due to what I'll call the merging of things into the same form largely driven by computing. For example... Icon for a phone - rectangular screen Icon for a TV - rectangular screen Icon for a tablet - rectangular screen Icon for a camera - rec…
Anecdotal evidence: when I first encountered a floppy icon, its purpose wasn't obvious to me at all, despite I've already used a floppy before. See the Chinese writing example in this thread as well. Apparently, prior knowledge of the real-world object doesn't affect usability as much as other visual features of an icon.
This makes me believe that, in future,
1) younger generations won't have any trouble with icons that represent old things they'll never see;
2) icon design business is going to profit.