Autodownload and auto caching for on the go

I have a 256gb iPhone and Wifi6 at home but due to my ISP’s slow up speeds it’s difficult to stream videos when I am out traveling. Unfortunately I often forget to download these files for offline in advance.

How cool would it be to “auto download” the up next items whenever I open the app on WiFi? (Eg download the next X gigabytes)

similarly, if I start watching a movie at home, how awesome would it be to auto download the file so that when I leave home I can easily finish the same movie.