Soviet literature of the period was definitely encouraged and even required to have ideological subtext, there's no arguing with that. However, that doesn't tell us much about how successful that policy was. The article is evidently trying to make a point that it was successful by presenting an example of a person who could recite "Barmalei" from memory, without mentioning that "Barmalei" was actually innocent and unrelated to the propaganda-infested books mentioned previously. That is either an error on the article author's part, or a purposeful omission.

Please don't read this as a claim that the policy was not actually successful (which I don't know whether is true or not).