Not always; the unknowable information in quantum mechanics is simply not there. It's not that there is no way to get at the information in practice, it's not e

Not always; the unknowable information in quantum mechanics is simply not there. It's not that there is no way to get at the information in practice, it's not even that there is no way to get at the information in theory. It's even stronger: Bell's theorem proves that the information can't be there: simply assuming that the information is there already leads to conclusions that contradict experimental facts. The idea that there ought to be information comes from erroneously applying our everyday intuition to quantum mechanics.