I've been advocating abandoning the foolishness of irrevocably dating the Eugenics War in the 1990s for a while. It didn't even make sense in the late 1960s. For Khan to have been a ruler of a quarter of Earth in 1992 or whatever it was, "Space Seed" was asking us to believe that there was a massive genetic engineering or selective breeding program being undertaken somewhere in the East even as the episode premiered.
Yeah, and whilst we're at it let's rename 2001: A Space Odyssey
If they rebooted Clarke's universe, maybe they should.
There's also the matter of reconciling WW3 with the Eugenics War, which imo is far more important than its chronological placement...
That said, I'd be willing to accept even this ridiculously alternative history as long as it didn't involve the Eugenics War being "fought in secret" ala the novels.