What is meant by Citizenship here is nationality, not civic behavior.

Nationality is nationality. Citizenship is not nationality. Are you arguing lexicography instead of etymology? Think.

A citizen is part of the city, surely. Prison is a village, and has precious few of the city privileges. Being in prison is citizen light, if at all. Being dead does not allow you to wander or contribute unless you have acquired and bequeathed that which you screwed from real citizens.

You can be an ex-pat in a xeno-city and be a model citizen - I submit, m'lord. While the words can be interchanged, like a "square peg in a.........." - they ain't equivalent, not even kissing cousins.

Merriam Webster thinks citizenship is :
1 : the status of being a citizen. 2 : the quality of an individual's behavior as a citizen. 3 : domicile

Hardly anything about passports ne c'est pas?