@Tutanota I cannot answer because I don't know what digital sovereignty means. Being independent from big tech, no matter which country. Being independent from US. Being everything self-hosted, I don't know.
"Sovereignty is generally defined as supreme, independent control and lawmaking authority over a territory. It is expressed through the power to rule and make law. Sovereignty entails hierarchy within a state as well as external autonomy, which refers to the ability of a state to act independently in international affairs."
If this is the case and I transfer it to my digital life, it means I own all my data and I am the only one who can control it. I have full autonomy over my own network data etc. That means it can never be achieved because I will never own voda or a telekom.