I’d say just as you can run your own server cooler (turn it off when not needed), Netflix servers are going to wind down during low demand and run lower power. But while you’re picturing you last laptop as a server vs a data center, try to picture every household out there running their own “server” the same way. Some are watching, some aren’t. I think OP’s question is more appropriate, comparing streaming to broadcast rather than streaming vs local storage. Besides, how’d you get that data? You transported physical media or downloaded it from a server.