Spotify recently pushed an update to the Spotify users which changes the Your Library UI and the way it works. Check this Spotify Answer to learn more about the changes to Your Library. Currently to sort Artists alphabetically simply swipe down in that section and hit Filters. Then chose Artist in the filters displayed.
They're always testing and launching improvements and new features, you can learn more here why.
However, if you don't like the new look, please head over to this idea and add your+VOTE. You can always add your owninput in the comments there as well :)
If you'd like more info on how the Ideas Exchange works, check more here.
Have a nice day :)
LoxerRock Star 16
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