I did not say that ipynb is more reproducible than .py. Using ipynb now is that best way for the millions of existing notebooks to be most reproducible with the leading notebook tools.
Replacing .ipynb as the standard notebook file format or changes to the format would be a community effort. The way to do that is the JEP process. It has the greatest likelihood for long term success and prevent fracturing the existing community which includes science, education, government, enterprise and others.
Not to sound like “it works on my machine”, I’ve used nbdime and it does a good job for diff. Personally, I haven’t needed more than that in my daily work. Though I understand others have different needs.
While a whole new format may seem like a simple solution, I suspect a new format will bring along its own set of deficiencies that are different from ipynb.
While flattered, I definitely do not have the bandwidth to lead this effort. I also do not wish to kill it. My recommendation would be for someone to document the “needs” and propose a mechanism for addressing those needs as a JEP.
From the millions of users standpoint, I see a radical change from ipynb as a risky move, and improvement to meet the desired use cases is a better approach. My 2 cents and I’m sure others in the Jupyter community could offer thoughts too.