I look around at the plausible suspects - Ukraine, Germany, France, U.K., Poland, Russia and one of the Baltics - and then I think about who's capable of doing this without a huge chance of rock solid proof of their guilt coming to light.
That gets me to either Poland or Russia. Poland has motive (keep Europe split from Russia), presumably ability and if it did come to light that they did it it would be really bad but not existential (I think Ukraine is out because undeniable proof of their guilt might cause real headaches for them)
Russia is odder because of motive. I can see two. One is financial - my understanding is that having a "third" party cut off the gas rather then they themselves doing it will allow them to walk away from contracts on futures. The second motive is that this is another "Cortez burning his ships" type move - something that makes rapprochement with the West harder and so gives anyone wanting that a tougher job.
Don't presume. Does Poland have the ability?
Not a single credible analyst I know of believes the USA did it. Considering the (excessive, IMO) care they've taken to avoid any escalatory actions they've demonstrated so far, it would be incredibly foolish and out of character.
Russia, on the other hand, is run by a reckless maniac who delights in chaos and constantly and provably lies about everything, all the time. So unless you have some very very compelling evidence or even theories to the contrary, I (and everyone else with even the slightest knowledge of these matters) will assume the crazy, lying bad guy who demonstrably did these other 100 bad things did this one, too.
So where is your argument?
However, looking at the behaviour of Russia recently with their non-linear war, $300m spent on information warfare, invasion of Ukraine, support of dictatorship abroad etc. who is the more likely to have bombed this infrastructure is highly debatable at least.
It just happens that Ivermectin doesn't do anything directly, and the people who were promoting it were evidence-based rather than correct. If Russia's "misinformation" is providing large amounts of true evidence then we need more of that.
That's been the pattern thus far.
https://www.politico.eu/article/germany-to-stop-nord-stream-...
> Germany is halting the controversial Nord Stream 2 pipeline in light of Russia’s incursion into Ukraine, Chancellor Olaf Scholz said.
Joe Biden was vocally against the pipelines. It's not a stretch at all, but let's just forget he said what he said, hey?
The conspiracy theory is that Russia destroyed a functional pipeline that it had complete control of. Why are the Swedes hiding their findings? The idea that they are covering for Russia is ridiculous.