Yes, if all goes well. And if global climate change doesn't crash technological society.

> If the world ahead has fewer people, will there be any real economic growth?

Of course there will. As long as per capita usage of energy and stuff increases faster than population decreases. Basically this will continue the concentration of wealth ~indefinitely.

I mean, consider Vernor Vinge's Marooned in Realtime. Even the poorest people consume as much as many nations do now.