Based on my understanding of this tool, it is simply a playlist generator. This could create playlists of Internet Archive content. If that is inaccurate, I am happy to be corrected.
Generating playlists is one of the things that Watchlist does. Here are a few more:
1) You can actually set very flexible notification schedules and use a medium of your choice (email, webpush) to receive the notifications about new/unwatched videos in a list.
2) You can keep track of your progress by marking the videos in a list Watched/Unwatched. This is good if you’re taking a course on YouTube.
A few things I am building in near future if all goes well:
1) Adding the “tags” functionality which will suggest similar channels to users based on the kind of videos & channels they’ve added.
2) A video summary feature which will send a short summary of the video to you.