Smart playlists are not displayed on cloud-based platforms (e.g. this webapp, sonos integrations, etc). I presume this is because they didn't want to implement the business-logic both on the server and on the native iTunes app.

I’ve never figured out why some Apple products are immensely well designed and some have basic aspects which don’t make sense and I guess it comes down to the people working on the products using them day to day or some exec who really uses an app day to day championing UX improvements.

Music in its current iteration seems driven by Apple’s need to become a services company and the music app which really last spoke to people internally was one in which your own music is portable, not a steaming music service.