Computer usability was better ten years ago. Of course, it were far simpler times. Windows managed all files. All document creation was handled by local apps very well within Windows (Word, Excel, Photoshop). All personal information was stored in a PST file in Outlook, including emails. The browser was ok for getting information. You only had on PC to care about, and Palm sync worked fine.
Look how things are more complicated nowadays. Files are in Windows, cloud services and iOS/Android devices. Mail, tasks, appointments are spread out among different cloud services. A lot of social content (facebook, twitter etc.) has no local app whatsoever. The information you need might be either in Dropbox, Evernote or iCloud. The browser is a central hub of activity but has no serious integration with the local file system. And so on. Not to mention that the computing is spread out among the main pc, a ultrabook, the tablet and the smartphone.
The tablets show the way of the future, but serious document creation is too complex for current mobile OSes. Managing multiple files, manipulating them with several apps, merging stuff, saving various versions, organizing blocks of work. 90% of the real work done in office by professionals does not fit in an iPad (Jean-Louis Gassée explored this point recently).
On one hand, it is quite a challenge to fix properly this huge mess, but this also represents a great opportunity for the visionary that eventually will get this right.