Maybe passing on files to children is not something most people will even have to worry about because social media stores everything forever. Once we've shared our life's worth of holiday photos with our kids on Facebook or G+, they'll still be able to access them after we're gone.
Maybe the things we want to pass on to our kids will be more tactile. Our first iPhone or 3d-printed wrench? Or maybe the same type of heirlooms that have been passed down families for generations - jewelry, watches, paintings. Sure we won't be giving handwritten letters to our progeny but frankly, that's our own fault. I haven't even written a single letter to my wife! And I don't want our banal "where u at" text messages to be memorialized for posterity. Our vacation photos or public blog entries shared online will do just fine.