No, the way it works is that there is a load balancer that terminates ssl and forwards it to nginx instances all in a private network. The nginx instances then have secure HTTPS connections over the public internet to the main load balancer that terminates ssl and forwards it over a private network the application servers. So this would be possible with any network since the cross country connections are encrypted.
That's a nice technique and the explanation is good while remaining concise.
We do something similar at work (I work in finance) where our clients connect to a secure gateway using HTTPS but all communication with our other services are made using an unsecure protocol.
If it lives in your house then it's likely to be harmless!
