The point is you don't provision your own servers, not that servers don't exist somewhere executing your code. People seem to be taking the marketing too literally.
Serverless implies that a server is not required after an installation step and that you only need your local device. Or perhaps too that you only need a collection of like clients to do something P2P.
Just because you as the developer don't have to think about the server doesn't make it serverless.
They say after all:
"and then unit and load tested it, all without using any servers."
...with a title of "Microservices without the Servers" when what they mean is
"without provisioning any servers yourself" which is obviously much less attractive.
My curiosity was peaked by the title the title, inserting "w/o provisioning" would have not gotten me anywhere near as interested in the topic.