If you earned billions of dollars over decades with software that puts groupings of files into things called folders and your customer base absolutely knew that folders are groups of files then whenever you made a new product you would call groups of files folders, right? WRONG!
If you have videos, since 1970’s TV’s had channels, you would call groups of files channels. Once I realized that channels were roughly synonymous with folders Microsoft Stream made more sense to me.
Channels are things you create so that you do not have to look at a list of every video you ever created all together. You can look at subsets of every video you ever created. They have no influence over who can or cannot see your video.
Groups can control who sees your video, You can create groups in Stream or use other 365 groups like those created in SharePoint or Teams to control access as long as you also uncheck everyone in the institution.
As you can tell by the tone of this post I was either particularly obtuse or Microsoft was particularly nonintuitive. But, I thought I would share my channel/folder metaphor in case it helps anyone else.