I dug out my scan-with-digital-camera setup, just to see if I still think it's more trouble than it's worth.
Tethering to Capture One on the iPad then using "Cloud Transfer" to my Mac works great.
But then I use Negative Lab Pro in LrC to convert to positive, which means I'm using both C1 and LrC, and also I have both a giant DNG and the converted TIFF to deal with. Not sure that it's easier than using a flatbed, in the end.