If we had to write every single piece of code over and over(or pay for them), computer science would have barely evolved and would not be so mainstream
The concepts of compilers, operating systems, databases, file systems, computer graphics all evolved from the 60s to the early 90s.
After that, it was mostly scaling.
And the open core licenses of nowadays are nothing more than a rebranding of those kind of license models.
If this is the way computer science evolves, it is safe to say that it evolves at the same pace as life.