When a song (or any content for that matter) has been deleted from Spotify probably because the person uploading it has decided to remove it. That song is unavailable and is Greyed-out in the Playlists. We (the users) have difficulty finding similar song replacements and sometimes there isn't any, however should something turn up later there is also no means of knowing it has.
So I suggest:
This may sound a complicated idea, most of what's needed to deliver it seems to already be part of Spotify.
Updated on 2020-02-24
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