Gobekli Tepe is just an earlier marker of OUR civilization.
The article is talking about earlier eons. Part of what makes the thought process interesting, is that all of the land masses have been turned over since an earlier "modern-type" civilization would have existed. So nothing they built or manufactured would have withstood continental drift, erosion, and being turned into magma and back into land again.
That's why they are looking at the carbon record. There was a big spike - similar to the industrial revolution's carbon spike - several million years ago. Which COULD be interpreted as an industrialized society developing to the level where their pollution was measurable on a planetary scale.
It's a fun thought experiment, and requires some rigorous, out of the box, scientific thinking...