Without the hope of technological progress, human expansion and economic growth the world becomes zero-sum.

In such a world, humanity will soon arrive at their self-imposed limits, after which no-one can hope to create wealth and prosperity but only to take it from someone else.

The pre-industrial world was like this and it is characterised by millenia of warfare and slavery. Human suffering on a scale that we struggle to comprehend.

Of course, some people are overly optimistic about the near-term possibilities of technology, but I much prefer that to the alternative.