I meant more at an individual level - like if I use 100gb of bandwidth today, and 200gb of bandwidth tomorrow there's a good chance that the extra power consumption on at least some of the network from my extra bandwidth is zero if what I described in my previous comment is the case.

If everyone attempted to double their bandwidth usage tomorrow, then yes equipment is going to have to be upgraded. (Although even that could be a case of upgrading equipment that provided N throughput and cost Y watt hours before to newer equipment that provides 2N throughput, and still costs Y watt hours)