We would not need a router or firewall. Probably not a wifi either. All stationary devices will be wired in. And mobiles would use 6G or 7G. Where I live (sweden) you can already get 10Gbe. Now imagine the possibilities. For example VR with less then a ms latency to closest datacenter. Where your device is just a thin client. Microsoft are already planning to build a DC near major cities, hopefully they are up to something cool.