You can do it, but not in the UI. This How-To explains the entire process.
You’ve done most of that already. The one step you need is this: after you’ve created your filters and applied them, but before you create the Playlist, edit the URL in your browser’s address bar. Below is the step in that How-To (search the How-To for “random” and you’ll jump right to it):
- click in the URL of your browser, scroll to wherever the “&sort=” keyword is (like &sort=originalTitle), change it to &sort=random (removing the original column)
Once you’ve created the playlist, every time you open it or refresh it, the order will change
