Except … it is. It’s just bloody hard to find. The PBS Channel Search menu searches only “Videos”, not “Shows”. To find Shows you have to scroll around … and around … and around… the “Shows” screen. Good luck with that. Once you find a show you can add it to Favorites.
I don’t know if this is something PBS can fix or if it’s some sort of Apple malfunction, but … wow … needs a fix. At the least Search needs to include Shows.