"Realistically, most people just drag stuff to a USB stick periodically and that's good enough for backup. That's how it really works."
Most of my friends and colleagues say 'what is a backup?' when I ask.
So a sync to a skydrive account may be better than what they have already, but I think the OA was saying that Win 8.1 could have made a genuine backup easier to do and less 'technical', thus improving data safety.
Instead the Microsoft people chose a different approach. The OA thinks that once people lose files because of an infection or corruption of storage, and if those files are synced large scale data loss will occur, and users will blame it on Skydrive.