I've seen multiple allusions to this idea without a firm grounding in historical fact. The suggestion is that the concept of multiple criminals and unrelated acts fit more easily with the communist world-view than that of the lone killer. This would seem to be reflected in the originally hampered search for Andrei Chikatilo.
Did the USSR genuinely perceive certain ills, including serial killing, but be indicative of capitalist society and not inherent in human nature?
Unfortunately it doesn't look like we're going to get a reply on this, so I tried to look into it a little myself.
'The Red Ripper' was a man called Andrei Chikatilo (also referenced as The Butcher of Rostov), who murdered at least 53 people in the USSR from 1978 onwards. It was well over a decade until he was finally caught, possibly because the concept of serial killings was not recognized within Soviet ideology. This is what interested me in this instance.
Without a more specific range of literature I have only been able to find a text by Robert Kalman, a Russian-born Canadian police investigator, published in 2014. I did also come across a researcher working in this specific field, but unfortunately that work has yet to be published.
In 1925 all Soviet studies into the philosophy and psychology of criminality were centralized within the Moscow Government Institute of Studies of Crimes and the Criminal. From this time and throughout the following decade such studies became increasingly focused on Soviet ideology. A Communist society, according to the ruling Soviet regime, did not produce crime; any serious social ills were anachronisms from pre-revolution which would eventually die out.
In this climate the study and research of psychopathy and killing soon degraded. Kalman claims that those refusing to have their work impinged by this trend were frequently fired, persecuted or even murdered. Serious crime therefore remained merely a symptom of error which was redeemed through hard labour.
Kalman continues that this state of affairs created a society unsuited to confronting serious crimes like serial killing, preferring to instead claim that such aberration existed only in the Capitalist West. Experts and law enforcement agents were often inhibited from even suggesting an alternative theory, lest they incur the wrath of those more doctrinally orthodox.
For these reasons, the USSR supposedly became a victim of killers such as Chikatilo, because their strategy of avoidance had degraded their ability to properly identify, profile and ultimately detain serial killers. Agencies therefore laboured under the false assumption that linked murders were in fact random anomalies. Kalman claims that these counterproductive strategies endured until the very final years of the Soviet Union.
Hopefully this was illuminating and thought provoking. I apologize for not providing an exhaustive explanation, but the history of the Soviet Union is not my field of expertise. If anybody knows/finds more, do please add it.
I think the recent Grandma killer is interesting.