America has a current embargo against Cuba.
Emphasis on "current". It's futile to argue about lasting effects when only an eyeblink has passed since the end of the event itself.
Essentially, all the effects listed are merely a return to status quo. Korea was split before the Cold War; situation remains. Germany was united; situation restored. The US was the technologically superior adversary but not outright military enemy of an ambitious Russia under authoritarian personal rule; situation restored. The US and Russia tried to expand their spheres of direct political influence through proxy wars, and now the wars are in the past and the influence is gone; both sides have humiliated themselves in Afghanistan, for example. And even that isn't merely situation restored, it's a no-event in world history, because
everybody humiliates himself in Afghanistan sooner or later, be it Alexander the Great, Ashoka, or the British Empire.
You keep bringing up the Spanish succession but that has nothing to do about a Russian man knowing his Russian history.
Actually, that conflict is the very reason there could be a Cold War in the first place. That conflict drew the lines between the British and French empires that enabled the United States to be born; that conflict delivered Russia from the persistent threat of its annying northern challengers Poland and Sweden and enabled the rise of that superpower, the reign of the Greats that Chekov so fondly remembers. That conflict also split Europe to suitably sized pieces that could become a battlefield between the later superpowers, instead of being a monobloc world dominator itself.
The only significant difference there is that the Spanish succession issue is 600 years in the Trek past while the Cold War is 300. Since we don't remember the 300-year-old chain of events that shaped our world, there's no particular reason why Chekov ought to, either.
Doesn't mean Chekov would be particularly uneducated. Everybody here is keen to prove his knowledge of events 50 years in the past. Chekov might have been well educated on those, too, knowing the history of the UFP/Klingon conflict in painstaking detail - especially the role of Russia in it...
Timo Saloniemi