What you are talking about is a typical Malthusian understanding of reality. At some level, there are physical limits that cannot be exceeded. On a practical level, those limits are vastly beyond what we can currently comprehend or use, and the entirety of human history is a testament to doing more and more with less and less. (With blockchain technology being a notable exception of always doing the same amount of stuff with more and more resources)

Also, as a small aside... the concept of an externality is not about pollution or waste. It is about a cost that is imposed on people other than the individual responsible for the cost. The finitude of the planet is immaterial to the existence of externalities.