I noticed that as well after reading the documentation. Here are a few other ideas.
Recently Played
https://developer.spotify.com/documentation/web-api/reference/#/operations/get-recently-played
before/after would only include songs from today. 50 max and then do a count of unique songs, most played song on that day would be the tag.
Currently Playing
https://developer.spotify.com/documentation/web-api/reference/#/operations/get-the-users-currently-playing-track
Have a tag option called Music. If a song is playing on Spotify, when the tag option "Music" is selected, it will pull in the song that is playing. Once again, this would be a little more manual on the user's end...because they would have to play the song they want to be pulled in, but I think it would work for those interested in this feature.
Saved Tracks
https://developer.spotify.com/documentation/web-api/reference/#/operations/get-users-saved-tracks
Not sure, on average how many songs people save in a day, but you could pull in the maximum of 50 and see how many are from that date; putting in tags for each song.