I can't help keep remembering how 'utterly unthinkable' it was (for most folks by far) that the USSR would actually collapse. Even in the weeks before... It did.
Anyone can say 'it was obviously coming'... in hindsight... but I was an aware adult through the 1980s (30 in 1988) and the 'fall' of the USSR just wasn't a topic, certainly not in the mainstream.