Versions of Ethernet has been around for many years, since the original Alohanet and introduction of CSMA/CD. It has evolved since then and beat out competing technologies. Packets of data will be coming to your PC to read this message over carrier grade Ethernet. 802.11 (WiFi) is in any case pretty much Ethernet over wireless.
It is true to say, however, that it is more of a niche techology at home as people don't tend to wire up their homes with the stuff like I did. Wired will, however, be better than wireless for some time to come.
Roku offers the Ultimate in the UK, which is wired, sadly not in the UK (only as a Now TV box)
Considering that a lot of homes have ISPs with gigabit or faster speeds available today for customers. However, Roku would make a lot of local streamers happy with a gigabit port, more so than a gigabit port for ethernet streaming over the internet. It will happen someday that a roku tv or streaming device will ship with a gigabit ethernet port for streaming over the internet when the bandwidth requirement meets a gigabit for streaming over the internet.
"The Ethernet Alliance's 2020 technology roadmap expects speeds of 800 Gbit/s and 1.6 Tbit/s become IEEE standard after 2020, possibly between 2023 and 2025. Doubling to 800 GbE is expected to occur after 112 Gbit/s SerDes become available. The Optical Internetworking Forum (OIF) has already announced five new projects at 112 Gbit/s which would also make 4th generation (single-lane) 100 GbE links possible."
I'm sorry, but 1.6Tbps of ethernet connected speed wont satisfy most consumer streaming requirements. I really hope we can stop using this slow outdated unevolving digital interconnect technology!