Eventually we will reach that point. What happens when we do? How does it affect our economies and societies?
There have been very long stretches of history in which general human progress was stagnant.
Productivity growth will eventually slow, given that we are limited in what we can do by the laws of physics.
Of course I could continuously rearrange superficial designs of things, which may give me an infinite number of things to do, but that doesn't increase productivity. There are a finite number of ways to do something in a more productive and efficient way than previous methods.
Given this, eventually we will reach a time when we can't make any more progress in the traditional sense.
In fact, I think we're starting to reach a plateau in the last 10 and the coming 10 years. With the exception of medical science and the entertainment industry, I feel there hasn't been much meaningful innovation that changes consumers lives. Sure, we have google maps and millions of apps, but honestly, 10 years ago, I didn't have any problems finding my way around the road, even if I had to draw out a map by hand (lol). Today, Transportation is still at the same speeds and costs, housing costs even more, medical insurance is everybit as expensive, etc.
The most dire forms of innovation needed by humanity today, are at the bottom of maslow's heirarchy of needs: shelter, food, water, and by necessity: transportation and medical insurance. These areas are not being worked on, due to the above reasons i mentioned.