I don't think we have a good enough idea about all the implications of quantum theory (like quantum gravity, or an answer to the question about whether space is

I don't think we have a good enough idea about all the implications of quantum theory (like quantum gravity, or an answer to the question about whether space is discrete or continuous, for example) to throw around claims like it's over for the code-breakers. Such claims, viewed in a historic context are always arrogant in retrospect and are quickly proven wrong by new discoveries.