We have over 650 songs now, ... So either words on a head chart on screen gets me by.
I have only around 100 songs, but we do the same because the screen allows us to index and/or search for a song, and we're not all leafing through folders or fake books. Most such apps allow playlists if one wants them.
The only time I use paper is if I'll be in sunlight as the screen struggles with that.