I guess you can't please everyone, but I actually found the lack of sorting new playlist items useful, as I built playlists. Often I would add items and then decide I didn't want them in the playlist. By having them all at the end of the playlist, in the order that I added them, I could easily keep track of things.

I hope you will reconsider and put the sort arrows back.

Removing them did nothing to change the behavior, and I think showing them actually provides something useful. My opinion.