I think three things are needed: standards, tools, specialization.
For example, we need standard ways for models and art to be packaged and reused, we need better tools for automating the process of reusing those standard component, then we need divisions or independent companies to build these components and sell them for use in many games.
A simple example is foliage, if there was a company that made great foliage with lots of customization options and it could sell it to many developers it would be cheaper for the developers yet that company could still make money.
You see this pattern in all industries as they mature.







