I would think of the desktop app as being an IDE built for beginners with free project-based courses built in. Any good IDE realistically has to be a desktop app so that it can integrate deeply with your OS.
Didn't mention it in my original post, but there's a premium membership that offers an integrated AI tutor to provide live feedback, explanations on course materials, and automatically tailor the course to the user, their experience, and their system. I also didn't mention that I'm very close to an MVP.