Aren't even the "high quality" 4k streams like 15GB/movie? So at $20/TB that's ~$0.30/movie at streaming quality? And you could still have probably better than DVD quality that people used to pay $20 for for like ~2GB, or $0.04.
Of course then as another comment here said, you're more likely to realize you don't actually want any of it. And then when you realize it's not worth pennies to store, you also realize it's not worth your time to watch.
This is about $/TB on bigger drives. If you only want a 1TB drive it'll be more like $50.
Don't get an SSD, far too expensive.
A UHD movie with UHD and dolby audio and all that is anywhere from 50 to 70Gb. That's if you rip it straight off the disc.
You can shrink it a little by being pickier about which audio tracks you take, but not much.
You can do other things to it to make it smaller, but then it's not the equivalent of the physical disc
2 Mb/s is awful for anything with movement, 8 Mb/s is decent enough, 20 Mb/s is very good to my eyes, and 80 Mb/s is nice, clearly better especially in scenes with significant movement, but it's not revolutionary. I don't watch webrips unless there's no other option, it's mostly WEB-DL or bluray rips.