I of course did not say you can, I listed open source as merely one requirement for a certain kind of sovereignty. If you really wanted to limit it to european contributors that would be covered by "governance" but I take the view that it is not the case that you need to have every single contributor subject to a certain jurisdiction in order to achieve sovereignty so my governance requirements would be more about ensuring that the development and decisionmaking process is not and cannot be controlled by a foreign entity for example.

One part of this discussion is in fact about what exactly we mean by digital sovereignty as it is not a fully established term and the way "sovereignty" is used in other contexts is not necessarily the right one or even give a complete definition that would work here.

I would also add that we should look at it as more of a spectrum than a binary because it's probably impossible to at once come up with software and services for every single purpose that satisfies the ideal criteria. Some projects will get us closer to sovereignty than others. Proprietary software is unlikely to get us very close at all unless it is government-owned as anything short of that means it could be transferred to a US entity at any point in time.