Here is an article, asking four historians how the USSR might have survived.
https://www.historytoday.com/archive...=pocket-newtab
Nearly all of them think that Gorbachev's reform attempts started the avalanche, but I think they also think collapse was inevitable. One posits that had the USSR retained total control of the media, like the current Chinese CP, it might have been able to do so.
So, I'm now wondering if any attempts to "revise" the real timeline with the point of departure of the 1991 coup are too late. Perhaps either the death of Andropov or the accession to power of Gorbachev are better PoDs? Or we accelerate the background timeline to a Twilight:1990?