If you recall, Russia had just shut of the gas - unilaterally and arbitrarily - 1 month earlier, so Russia was legally liable for billions in damages for non-performance in valid delivery contracts
But, with the pipeline destroyed, Russia had a legal excuse not to deliver, saving billions
yes, cui bono
Hmmmm … obviously, I don’t know who blew up the pipeline, but that’s an interesting financial motive/reason for Putin to do it.