Not really - you can increase productivity, the end game of that being full automation.

Lifespans are increasing and automation claims turned out over optimistic so far - if you are close to retirement the last thing you want to see is a shrinking working population, shortages and inflation.

Each generation doesn't have to be bigger than the last. Two people create two children, those two children create two children, the grandparents die, the grandchildren create two children, etc.

That stabilizes the population (technically population goes down due to accidental deaths, diseases, etc. but you get the idea).