Hi @konsta, what a great question! It goes to the heart of maintainers here
The documentation is mostly written by the same people who develop plotly.py and Dash.
For plotly.py, the documentation source files are in https://github.com/plotly/plotly.py/tree/master/doc/python. It consists of Markdown files which can be opened as Jupyter notebooks thanks to jupytext. If you’re looking for ideas, there is an open wishlist for examples in tutorials https://github.com/plotly/plotly.py/issues/1965
For dash, the documentation source is in https://github.com/plotly/dash-docs (the Dash documentation is itself a Dash documentation).
For both packages, feel free to open an issue in the relevant repository to discuss a documentation idea which you have in mind, if you would like to have early feedback abut its relevance.
Thank you so much for offering your help! Looking forward to more discussions on Github!