How do you copy a bunch of documents and pictures to a USB drive if you don't have a full filesystem? "USB drives are outdated, use the cloud" is not a valid answer so don't even bother saying it.
It's apparently hard enough that no one's been able to provide a better solution to the general problem yet, only specific instances. (No, the iPad doesn't count because it doesn't even have a USB port.) So instead of researching pie-in-the-sky solutions (which is incidentally what MSR does), they've decided to invest resources in something that we know works to the extent that it does.