These sources seem a bit pro-russian/anti-US/Nato conspiracy theorist, but honestly, I think I agree with them that destroying these pipelines would be both the best thing for the EU/Europe and the worst thing for Russia, so I could imagine some governments at least considering this move. Or environmental terrorists, do we have those yet? It's a "burn your boats" style game theory commitment to getting off Russian gas.
On the downside, it removes a carrot from the negotiations with Russia to de-escalate the current situation, as there's no easy way for them to start selling to Europe again after they lose the war. So, based on that I'd be dubious that it's a government action. Probably depends on timescales for fixing them.