Well post-Stalin the U.S.S.R wasnt anywhere near as repressive as it had been in previous decades. So in reletive terms it's improved since the early 50's while the USA fell off a cliff. And there were always fair-sized reformist/non-Stalinist factions within the CPSU. Even after Stalin had purged the hell out of it...Several times, had things been otherwise Gorbachev would never have gotten away with the reforms he did OTL.
I just get the feeling with the Disney and later Stennis causing all this crap (wittingly or not) such as using metal hospitals to imprison dissidents would discourage the U.S.S.R from doing the same, if only for Agiprop reasons. The combination of factors. Such as the large influx of African-Americans, the near-by cultural renaissance happening in Europe, the changed outcome in Hungery, the Middle East and the apparent social breakdown in America (the author said In elsewhere that the Soviets see the US as being in decline) will take considerable Cold-War-paranoia-fuelled ‘’America will destroy us if we ever let our guard down’’ pressure off the Soviet regime