The Borg still adapt even if they use a randomly changing sequence, which means even in the future of Star Trek, they haven't actually found a way for computers to generate real random numbers and it's just an algorithm to simulate it, which of course the Borg can extrapolate from.
You'd think they'd have quantum mechanics on lock by the 24th century.
That's an interesting idea, although I'd say in that case they just "meta-adapted", so that even truly random variations in the same degrees of freedom would not have helped.