Earlier quoted context omitted.
The question, then, is why not have the state university build the tests and write the textbooks? Then you fund the actual creation once and can straightforwardly fund updates and alterations as needed.
State universities are not good at doing either. There are not enough psychometricians or test writers or textbook writers in psychology or curriculum and instruction departments. State government is not better at doing things than big companies. Hope your solution is not to ask the government to do everything.
Many of the big tests are developed within an academic setting with university/public funding then licensed out. Almost every book is written by university professor then published by pearson or others.
State government does not outsource writing the tax code or the other regulations to companies why is tests any different ?