I don't see why data rendundacy and backup would require device rendundancy - especially for the common person. After all, I don't have two lights in every roo

I don't see why data rendundacy and backup would require device rendundancy - especially for the common person. After all, I don't have two lights in every room in my house just in case a light bulb blows, I just buy a pack of lightbulbs. In the case of a drive failure, there should be a way to recover data loss, but this shouldn't be ever present and visible. As far as simulataneous device usage - I'm not sure I understand what you're saying. Most brains can be thought of as single threaded working with multi-threaded multi-core parallel executing devices. The limit in doing multiple things at once has always been biological in my case. For things running in the background - this can be done with current technology.