I don't follow your logic. Just because companies could grow their businesses without increasing their workforce it doesn't mean that they couldn't achieve a higher rate of growth by increasing their workforce.
We see it all the time? Google's revenue is up last quarter despite redundancies meaning they have a lower headcount. Adding robotics to a car production line can massively increase the productivity of a single factory despite needing less headcount, often allowing other factories to shut.
Something like Intellij or Copilot can make the entire tech workforce more efficient _far_ in excess of what it cost to make.