Its extremely likely that the Soviet Union used far more resources to maintain control over the small republics and it's conventional military presence around t

Its extremely likely that the Soviet Union used far more resources to maintain control over the small republics and it's conventional military presence around the world than it did in tail end of the space race, the former two becoming even more expensive with the political uprisings and occupation of Afghanistan in the 80s. We're talking about 1-2 orders of magnitude here (no citations but the USSR was more populous than the United States so the numbers would be in the ballpark). You can argue that this is the final straw that broke the proverbial camel's back but there were many, much bigger straws that had already done so, it's just that camel took a while to collapse under its own momentum.