Thanks for comment and providing the review to my post.. Let me answer it in various steps.
For various reasons, I cannot move the entire MadAnalysis project to GitHub. The main of these reasons is that this code is widely used in the particle physics community (the three corresponding articles are gathering several hundreds of citations as a proof) and I don't want to confuse my own community. However, the Utopian-MadAnalysis project has nothing to do with the development of MadAnalysis. Having the main MadAnalysis repository on LaunchPad instead of GitHub is therefore not a blocking point in my opinion. None of the tasks done within this project will impact the core code.
The idea of this project is to work on the Physics Analysis Database of MadAnalysis. This database is a collection of external contributions that are stored on Inspire (again not GitHub) and that allows to associate a DOI to them, so that they could be cited in physics papers. This project is to develop some of these external contributions.
However, what matters is that the finalized code is submitted to Inspire to get the DOI. This does not prevent the development to be done on GitHub and be mirrored to Inspire at the very end. I can even connect the main program to the github repository as well if necessary.
This is what I had in mind actually, and I think that it fits the Utopian rules so that there is no need to make any exception.
Note that I am fine to continue this discussion either here or on discord (I am not planning to post the next episode before next week anyways, or at least before next Friday).