with the odds being good the same data could be served at 1/20th the cost today
Gotta nitpick you there. According the Moore’s law (really more of a rule of thumb), the price of the silicon used to serve those videos should be 1/16 of what it is today. I’m not aware of any corresponding law that describes trends in energy consumption. It’s getting better for sure, but I’d be shocked if there was a 20x improvement in 6 years.