Apple has finally released a web interface for your service Apple Music, thus adding functionality that most streaming services like Spotify, Google Play Music or YouTube Music already offer.
Web access to Apple Music is a very useful function for users to listen to their library anywhere. It arrives with a dark mode and has many of the new design elements of Apple, so it looks better than iTunes.
The service is in beta but, if you are already subscribed and want to access your music library without installing iTunes, try trying it at beta.music.apple.com.
This website too seems to suggest that Apple prepare a playback application for Apple Music for Windows since there is a button to install Apple Music that, for now, only launches iTunes.
Taking into account that Apple is saying goodbye to iTunes on macOS and building an independent music application, this may happen soon also in Windows.