> I don’t even understand what the author wants here. There is no such thing “truly serverless”

The author says what they want. It's literally their next sentence:

"As in, I don't want to think about future resource needs, I just want things to magically handle it."

and they have four bullet points with examples of what this means to them earlier.

I think it's fair to argue about the desirability, achievability, etc of this. I don't think it's fair to act as if the author is just spewing buzzwords without explanation.