I bet if these media conglomerates on their streaming services started offering DRM free unmolested mp4 digital downloads and sell their movies and shows at a reasonable price, people would buy that up. For instance a recent Sony movie, The Equalizer 3... $12.99 for DRM free MP4, yes I would buy that and keep it on my NAS. I might copy it to my laptop to watch it when I'm on a flight. I can make a backup copy and not worry about losing access to it. Yes, I would pay for that. Would you?
In theory it should be cheaper for them to sell DRM free files of their movies and TV shows than hosting a streaming service, but most customers will only need to download it once. Where streamers will often watch the same video two or even more times. That is a lot of bandwidth being wasted.