Then it would be incompetent. There is political resolve against Russia in Europe. Keeping the ability to bomb the pipes is one thing. Doing it in the midst of that resolve would be self defeating.
Surely it cannot be completely outside the realm of the possible that Someone(tm) helped EU politicians do The Right Thing(tm) by ensuring they couldn't give in to Russian demands this winter even if they'd wanted to?
(I believe this one's on the Russians - but I can see other actors finding it beneficial that Russian exports cannot easily be resumed. Especially as long as the Kremlin denying it had anything to do with something is largely seen as evidence it did indeed have something to do with it.)
Could be. But doing it now and like this (three simultaneous incidents that are also highly repairable) would be stupid. If it’s American it’s because placed mines went off early.
(Presumably the water inrush is slowed by the escaping gas sufficiently so that the pipeline doesn't sustain further damage, but I'm just guessing. Being an electrical engineer this is way outside what I dabble with on a day-to-day basis)
I would believe it more likely to be the Russians testing the waters, so to speak - finding out how far you can go sabotaging infrastructure.
After all, starting with two non-operational pipelines makes consequences less severe at both ends, while gaining the perpetrator some experience how to evade detection. (Which may come in handy later!)