>NS2 was not quite German infrastructure, it's really Russian infrastructure

What are you talking about? Western companies literally own half of NS2.

>no gas ever has flown through it and none would have almost certainly even if it were still fully intact (one strand is undamaged)

I wonder if intentionally delayed certification of the pipeline by Germany has anything to do with "no gas ever has flown". The point is: NS1 + NS2 was a constant temptation for Germany and blowing it has removed the "wrong" incentive.