One of the more interesting take-home lessons is that low-tech systems are a good passive defense against high-tech cyberattacks (aka, 'going autistic'). From the linked Nov 30 Economist article, "Lessons From Russia's Cyber-War in Ukraine": https://archive.ph/MJP0J > "Ukrainian resilience was helped, paradoxically, by the primitive nature of many of its industrial-control systems—inherited from Soviet days and not y…
Russia has an interest in sowing energy chaos amongst European countries. When dealing with a personalist dictatorship one has to take into account the state of mind and beliefs of one person and such a thing can be erratic and irrational. One should also take into account rogue elements within the regime. Perhaps oligarchs are vying for power by sabotaging other oligarchs who are also vying for power.
There was as much energy chaos before as there was after.
The presence of a stopped pipeline simply meant that there was an off switch on the energy chaos in Germany that could be flipped - presumably a switch that comes with Russian strings attached.
Somebody was pretty desperate to remove that off switch from Germany's hands.
It's also a switch that, if flipped, would render a multibillion dollar investment in LNG port capacity instantaneously worthless.