Being able to have a proper file system where we can utilize some of the memory for storage would be helpful to me. Apple has never allowed such a thing except for some work around. I use one of my 10.5 iPads out in the field and sometimes so far out in the boonies that my cellular will not work. I need access to my company's customer contracts, over 4500 with double that archived. Also need images taken with a file manager to keep them in order, sometimes hundreds of progress images a day. Moving these images around in Apple's way is a pain.
But you've always been able to store all that stuff. You could store PDF documents for your clients (assuming that's what they are) with iBooks for instance, and the photos in Photos.app or a huge variety of other apps.
And besides, the Files app is just another sandbox to put stuff into. Except that the app itself is only a file browser, it's storage mechanism doesn't work any differently to iBooks or Photos.
You do not find a real file system nice to have?
I think it's nice that it's there, but I don't really use it as of yet.