> Yes…is there something preventing you from doing so?

Full multitasking, which is required for the hours or days it takes for such a long upload, and ability to connect an external hard disc.

> if your hard disc supported a format that iOS could understand, such as a lightning cable, Bluetooth, or Wi-Fi.

Which is to say, hardly any of them.

> There are apps that let you do this.

Show me some that still work. I looked but couldn't find.