They claim that streaming over WiFi to a single mobile device is 37W:

  Because phones are extremely energy efficient, data transmission accounts for nearly all the electricity consumption when streaming through 4G, especially at higher resolutions (Scenario D). Streaming an hour-long SD video through a phone on WiFi (Scenario C) uses just 0.037 kWh – 170 times less than the estimate from the Shift Project.

They might be folding in wider internet energy usage?

https://www.weforum.org/stories/2020/03/carbon-footprint-net...