I can say that every finite computational problem can be solved in O(1), so if the universe is finite, all real problems can be solved in O(1).
This sounds great until you realise that the constant factors involved would overwhelm any practical instance of this strategy.
It means the idea isn't necessarily wholly impractical. That's not nothing.
I imagine superoptimisers scale extremely poorly, but that's a different question. I imagine they're best suited to bit-twiddling problems rather than, say, figuring out the best assembly code to implement a parallel Timsort.
I have to admit ignorance here though, I know almost nothing about superoptimisers.