I've often thought there should be an open code/data license that restricts usage and dissemination only to those who agree to make their code and data equally

I've often thought there should be an open code/data license that restricts usage and dissemination only to those who agree to make their code and data equally available. Why? Because in many fields there is a negative incentive to provide code and data. It not only takes time, but it opens you up to criticism by people who wouldn't be willing to make their own code/data available. Perhaps something like this would raise the bar and encourage more people to share their code/data. Just a thought.