> - Under a playlist you get a list of suggested songs, the UI element looks like a "regular song", but unlike every other "song" element the user has been trained to recognize, the "swipe right to queue" does not apply to these elements. For some reason.

There's a ton of these inconsistencies. For example, the new releases albums where songs become available over time also do not have it. It's infuriating how inconsistent the UI is sometimes.

Not so long ago they also had two versions of the "swipe right to queue" UI, one with long swipe (the current one), and one with a much shorter one. I preferred the shorter (with the hard break) one because it is much clearer when a song actually gets added to the queue. What often happens when you're adding multiple songs to the queue, if you only swipe a little bit, it is unclear if it was enough to add it to the queue. With one song this isn't a problem because a message with "added to queue" is shown, but for multiple songs, the messages are shown on top of each other.