* Mike Hammett:
Netflix recommends 25 megs for Ultra HD, while only 5 megs for HD. That's a 5x difference in something people likely won't notice and would make a big difference on the additional VPN, VoIP, video conferencing, etc.
4K isn't supported by all devices and plans. I'm not sure what kind of savings you can actually realize there. It could be that 4K content isn't worth caching near the edge. Then ditching 4K could still have a significant effect despite relatively low usage by subscribers. Similarly anything that reduces content diversity (like serving only one category of 1080p streams). Reportedly, the issue is backhaul capacity for some CDN nodes in Europe, and not capacity from the local cache to the subscriber, but I do not have any direct knowledge of that. Relaxing copyright and patent restrictions might also help, at least in the medium term.