Show me a streaming service will give 20 Mbit/s. Sure, they adjust the bitrate to your connection speed, but I'm sure most of them have a hard cap well below that of most high-quality satellite channels.
I'm paying $7 a month for tens of thousands of on demand HD movies and TV shows, that look like they're in HD. The images are crisp, clear, and have no pixelation, no ghosting. If it is delivering all of that at a fraction of the required bandwidth, why does the bit rate need to hit 20 Mbit/s? Should I pay more so that I can say I use more bandwidth?