What? You've been able to do that for a long time on Itunes, Google play, and Amazon. You have also been able to buy individual tv shows and movie physical copies at stores for decades.
Why is this a need? The minimum unit you can purchase is a month of service. You are free to subscribe and unsubscribe as many times as you want. I'm not aware of a single service that costs more than either a single movie theater ticket or a single newly released Blu-ray/DVD. So you are free to subscribe to HBO watch Game of Thrones, cancel HBO, subscribe to Netflix, watch BoJack Horseman, cancel Netflix, subscribe to Amazon, watch Marvelous Mrs Maisel, cancel Amazon, and so on. That is much more control and choice than cable subscribers had a decade ago. We don't need to make perfect the enemy of the good.
Try it on Windows. Or in an unsupported device. Or anywhere they don't want you to see it. You own nothing with digital. It's a long term rental. Also try passing it along when you die.
Try passing along a vinyl or CD or VHS or DVD collection when you die. See how fast it ends up at a flea market, or on the curb waiting for the trash truck. ALL digital goods are ephemeral one way or the other, unless you're an actual archivist. That's why archivists are important as their own discipline.
Nah, a lot of people actually do maintain vinyl/DVD collections. CD/VHS sure they may discard but that's because those forms of distribution were inherently flawed and degrade much quicker - VHS tapes stretch out, CDs get scratched up like crazy.
iTunes has worked on Windows since 2003. If you buy a movie on iTunes from one of the five studios that support Movies Anywhere, you can port your purchase to Amazon, Google? Or Vudu v