How much internal or extremal pressure was there following the Nuclear disaster?
The timing certainly seems to fit - a scant 5 years after V. I. LENIN nuclear reactor 4 in Pripyat exploded, the entire soviet Union dissolved. Shortly after - glasnost was implemented.
One of the recurring themes of the series is 'how much is the cost of a lie' - its well known that 'alarmism' was punishable by hard labour, and a pacified pliable populous was the aim of the party - one that listened to the truth of the party, however much it wasn't. And the cost of that lie - as the series implies - is the society itself.
Not to discourage further discussion, but with the release of the show, this question has been quite frequent. Here are two excellent threads for you to discover:
A popular and answered thread where the answer is basically, no, the top answer by
Kochevnik81 is quite concise:
And regarding your ideological premises, here is a pretty big and recent thread, with a gilded response by
Not to take away from your question, but you may also be interested in an earlier post here: Mikhail Gorbachev wrote in 2006 "The nuclear meltdown at Chernobyl... was perhaps the true cause of the collapse of the Soviet Union" - what role did the disaster have in the Soviet collapse?, with answers from /u/Kochevnik81 and /u/mazzikd.