Going from one release to the next does not represent a doubling of capability. It is an incremental refinement. Take, for example, an image processing program such as Photoshop. In some cases, later releases are not even an improvement on early releases. Some word processors become bloated with features, and are actually less convenient to use than the original program.
Compilers are a mature technology, like electric motors and steam turbines.
So are word processors, spreadsheets, image processing programs, etc. Each type of program goes through a series of refinements, until a mature product emerges. After that, improvements are asymptotic. This also applies to operating systems. After that, further releases will merely be refinements.