The entire point here is to not just handwave and excuse "incoherent beliefs", but to correct them. This is constantly met with shit like "don't let perfect be the enemy of the good" which is rightfully called out every time liberals wield it as a cudgel against us, but suddenly becomes acceptable criticism when you can use it to punch left yourself. The criticism you find so inexcusable is literally objecting to chauvinist apologia sentiments like "he made his reactionary posts two years ago, i'm sure he has changed", which is nothing but wishful thinking.
To be clear: I do not go anywhere near this hard on people outside of this site who express Adjuster sympathy, because i genuinely meet them were they're at, but come on. That's not who we're talking to on here. We are among commited, at least somewhat educated leftists who understand the need for revolution and the futility of incrementalist reformism. I do not need an example like the Adjuster to demonstrate to you that there are cases where political violence is a necessity if you want to prevent the greater harm that inevitably follows when capitalism keeps existing, i do not have to convince any of you that our liberation will not be achieved without hurting and violating the capitalist class. So i will hold you people to a higher standard than some libleft rando who just discovers that the bourgeoisie is edible. That is all, but it is apperently too much already.
I understand that seeing a CEO gunned down is a cathartic sight that has given the people on this site a hope they had thought lost. I fully do. But that this is possible is independent from who did the deed. When we want to engage in constructively moving average Westerners left through the momentum created by these events, we need to know where our criticism and disagreement with the Adjuster starts, and that is precisely at his ideology. That does not mean we should immediately react with "Luigi is a techbro douche and problematic, actually" every time the topic pops up, but we need to be aware of that fact regardless. To not be able to bear such criticism is the actual infantile disorder here, it is a symptom of hero worship that cannot reconcile the dissonance that is inherent in a flawed and in his ideology fundamentally wrong individual doing a good thing that impressed us. We need to be better than that.
Regarding your source, it should also be pointed out that the people Lenin demanded German leftists to work with had consistently been supporters of national chauvinism, war mongering and violent, murderous anti-communism. At the time of his writing, the social-chauvinist forces in Germany had already had Luxemburg and Liebknecht murdered by their Freikorps mercenaries, had sent in troops trained through settler-colonial genocide in Namibia to beat down the hunger revolts in Northern Germany, had crushed the Munich Soviet Republic, and had engaged in countless other openly anti-revolutionary acts of restaurative chauvinist terror. That's what happened immediately before this text was written. The trade unions at that time largerly formed the electoral base of the SPD that was actively gunning down communists who rose up against the capitalist order. Calling German trade unions in 1920 reactionary wasn't an infantile disorder, it was a correct description of these organizations and their widespread absence of revolutionary class consciousness. These were deeply reformist, brainwormed, liberalized institutions that posed an active threat to the German left and utterly and catastrophically failed to stop fascism in the following years. These were the people that made Stalin call social democracy "objectively the left wing of fascism" a mere decade later.
Lenin even recognizes this fact himself:
In countries more advanced than Russia, a certain reactionism in the trade unions has been and was bound to be manifested in a far greater measure than in our country. Our Mensheviks found support in the trade unions (and to some extent still do so in a small number of unions), as a result of the latter’s craft narrow-mindedness, craft selfishness and opportunism. The Mensheviks of the West have acquired a much firmer footing in the trade unions; there the craft-union, narrow-minded, selfish, case-hardened, covetous, and petty-bourgeois “labour aristocracy”, imperialist-minded, and imperialist-corrupted, has developed into a much stronger section than in our country. That is incontestable. The struggle against the Gomperses, and against the Jouhaux, Hendersons, Merrheims, Legiens and Co. in Western Europe is much more difficult than the struggle against our Mensheviks, who are an absolutely homogeneous social and political type. This struggle must be waged ruthlessly, and it must unfailingly be brought—as we brought it—to a point when all the incorrigible leaders of opportunism and social-chauvinism are completely discredited and driven out of the trade unions.
But the conclusion he draws from that is "you need to keep working within these reactionary institutions instead of building better ones that offer an alternative where class consciousness is fostered instead of recuperated" because he ascribes the reactionary disposition entirely to the trade unions' leadership. He somehow convinces himself that it is not shared by a significant number of their members, that it has been imposed on the masses top-down, that the reactionary insitutions are reformable. We see how that has turned out. This text is probably Lenin's biggest L, history has utterly crushed it. This is the same level of being wrong as Stalin's demand that the People's Liberation Army work with the Kuomintang in the Chinese Civil War. Why would you drag it out here?