Well, it sounds to me that the parent comment viewed a lack of autoplay as a feature, but it's nice to know it's actually an option at any rate.
I wish:
* the playlist was easily accessible from the left pane drawer
* autoplay was easily toggleable from the playlist view
* the automatically added title wouldn't be a regular title in the playlist before it's played (a bit lower and grayed, and adding items would do so above that title)
* the playlist would show various options for the next automatic title.
But nowadays, I don't really want to invest time in the Android ecosystem, especially as I think I'll switch my daily driver to a PinePhone soon enough. The desktop equivalent is freetube, I think.