So what’s your recommendation exactly? Nested playlists?
I admit to starting a blank as I didn’t really start listening to music until Apple Music, so the concept of owning music, much less a digital music library is kinda foreign to me. I am more a podcast person myself.
I'm less of a podcast (only following one actually) person myself, favouring my own 'curated' playlists above all else
As for my recommendation; earlier I mentioned some options to try, such as, a (draggable) button which can help you scroll at faster/more accurate speeds through the list. The button itself could appear when you are manually scrolling above a certain speed.
You could also try to add a 'index' from A-Z—or Z-A for that matter, to the right of the list. Since sorting alphabetically helps, but is still cumbersome when trying to reach e.g. the songs starting with a 'P'.
One could also introduce a sectioned-list where you can either make manual sections or pre-defined sections (again; A-Z) and allow people to scroll section-wide as opposed to per track.
These are just off the top of my head, I'm sure you can think of—or at least try more solutions as well. In the end it's about offering ways to index a list and make it easier to scroll through.
Just realised it may be helpful to know how people such as me use their lists as well.
I, for one, know my playlist and it's custom order like the back of my hand...weird as that may sound, and like to scroll to certain 'places' in the list at different points throughout the hour, day, etc.
Oh, just now thought of another thing which is already a big help.
What about adding a 'scroll to this song' whenever you use the searchbar on top of the playlist? That would make things already that much easier.