When changing country on iCloud, did you lose all your purchases (apart from subscriptions)? Like books, apps, movies…
It has to do with how the individual content (film, app, song) is licensed. If the same content has a separate license in the new country, it won’t carry over.
Also note this means it will depend on the two countries you are moving between (ie. I went US > UK, and I would guess there is a lot more licensing crossover between these two countries, whereas two others may not have so much).
1. It's DRM-Free.
2. I can remove the DRM. (All iTunes movies released prior to 2020 fall into this category.)
3. It's cheap enough that I can treat it like a rental; I fully expect to loose access after a few years and anything longer is a bonus.