In the article, they go over some examples of it being used in the mainstream by George Will. There's also at least one youtuber they cite as using it, for what that's worth. I haven't seen it on Hexbear or Lemmygrad, which is good.

From this article alone (never heard of this person before), they're definitely anti-Kautsky and pro-Lenin.

This whole section is interesting, too:

This quote is fake. More importantly, even if Lenin had said it, a sassy riposte to Kautsky cannot not "prove wrong" the idea that leftists should "convert people who think differently".

In reality, evidence overwhelmingly shows that persuasion works. For example, these three large-sample experimental studies strongly suggest that factual corrections change minds:

Wood et al 2018: there is no evidence for a consistent "backfire effect"; telling people facts generally changes their minds; among 10100 adults, the effect of factual correction was ~1/3 as large as the effect of ideology on stated belief

Schmid and Betsch 2019: experimental study: among 1661 adults, topic rebuttal (oppose misinformation with facts) and technique rebuttal (refute the methods that science deniers use to mislead their audience) substantially and significantly reduced the influence of science deniers (by about 1/3 of a standard deviation), especially among individuals who vulnerable to antiscience beliefs

Tappin 2021: against "partisan motivated reasoning": among 5071 adults, evidence changed minds in a sample of 24 policy issues; no significant difference between "evidence + contrary party leader cue" (purple) vs "evidence alone" (black)