Updating ipod from itunes
If you can’t update to mac OS 10.14 Mojave, you might still be able to get some updates for i Tunes (up to i Tunes 12.8).
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I've seen forms of this question asked within communities but never a clear answer.
From personal history, I can say that the "deauthorize" solution is useful if you don't have Apple Music but are still having sync problems. It's an option that lets your followers on Apple Music know what you previously played.
It also serves for better weekly music recommendations, as well as songs and albums you might like in is yet another option that has absolutely nothing to do with play counts.