You can download some Netflix content to your own device. Probably most if not all of their original programming, which is the direction in which they're heading anyway. You can also download some Amazon Prime Video stuff. Not sure about Hulu. And maybe your cable company lets you as well? (E.g., I think the Verizon Fios TV app). I can download the majority of programs saved on my TiVo. So there is plenty of ways to get "streaming" content onto your device without having to stream over the actual connected Wifi, you just have to plan in advance.

Also, I'm pretty sure that some international business class seats have video connections to the IFE, but not sure about which airlines or what kind of cable/device you need.

But I think these are separate questions. Seems OP didn't want to have to carry his own IFE device.