I guess I should have added that I know where the .ipynb originated, and therefor at least part of the reason why Jupyter notebooks (still) use the .ipynb exten

I guess I should have added that I know where the .ipynb originated, and therefor at least part of the reason why Jupyter notebooks (still) use the .ipynb extension, but I'm curious why nobody said, "hey, let's make this extension simpler", or when they did, why it didn't get enough steam to be implemented.