Hmmm, my post seems to have been eaten.

If there’s a course you enjoy, you need not lose access to it. You can go to the course, go into the individual lessons, and in the video player for the lessons there’s a “sharing menu” where you can individually download the videos.
It’s a little bit of work to download all the videos, one at a time, but if there’s a course you haven’t finished, that you really like, or simply believe you’ll want to revisit at some point, there’s no reason to lose access to it.
I create a “Cubicity” directory, then a “videos” directory under that and dump the course videos there. The videos are named sanely, with 01-VideoName style format, so they stay in order on their own. (With the leading 0s in the video name, they’re always in alphabetical order.)
Edit: Maybe the download icon that shows up when you click the “sharing menu” could be the icon used in the main player menu. It’s more obviously a download button than the pop-out looking button.