I think the argument is pretty simple: if you overrule the flags on any article that by a pretty simplistic reading of the guidelines should be flagged because (1) it is nationalistic flamebait and (2) does not present actual evidence even though the title pretends that it does by stating things as fact when they clearly are not then it is your own judgment about the veracity of the article that drives you to do so.
That judgment normally should not weigh as much as the combined judgment of the community members with flag powers. At that point you may as well disable the flags because your trust in the judgment of the community has eroded to the point of non-existence.
I think at best this should be presented with a title of 'How America could have taken out the Nord Stream pipeline' because as it is the facts are not supported by any evidence and there are some clear flaws in the article (for instance, see the comments by user 'weatherlight'). The reputation of this particular reporter was at one point in time absolutely stellar but has gone steadily downhill and I think you should update your priors as to whether you still want to stand by him when making unverifiable claims. Note that no reputable paper would put this in print, which is why you find it on substack, the place where conspiracy and controversy finds its audience.
Note also that this article essentially claims privileged knowledge about an act of war, gets a whole pile of details factually wrong and yet the main claim apparently should stand and get the benefit of the doubt, including a title that states this all as fact (those quotes and question marks are just confusing). Something that grave should not be amplified until it is presented with more foundation.