I also see a need for both.
Storing and cataloging printed music is easy. Buy a filing cabinet and manila folders or envelopes. Place said printed music in a folder or envelope, write the title and composer on the outside, and place it in the file cabinet in alphabetic order. Easy, peasy. Libraries have been doing something similar since the advent of printed text and the Gutenburg bible.
For digital cataloging, create a folder where you can store your scores. Copy the files there. If desired also create a spreadsheet and enter the name, composer, instrument(s), grade (if desired), and any other information/comments you want. The spreadsheet can be sorted on title, composer, or any other column. Again, it's not rocket science...
Digital is great when you need immediate delivery rather than waiting days for it to be shipped and arrive. However, once I receive it I print a hard copy to file away. The biggest drawback to digital scores/music/photos is people. People don't backup their files. One of these days, when least expected, everyone will have a hard disk failure and without a good, reliable backup, all your digital scores/music/photos are toast... If you are lucky, you might be able to pay $500-$1000 to have a recovery service get most of your files off of a dead drive, but you probably won't get back 100%.
"Never give a flute player a screwdriver."