One should think that this would enable anyone accused of a crime to argue "Your Honour, I could not know that my act was illegal as the law in question is unaccessible to me."
Fair notice is pretty narrow. I am pretty sure (could be wrong), that there is no requirement to codify even. If a state wanted, it could leave its laws uncodified and require you to go through every page of legislative records to discover what the law is. What it can’t do is pass literally secret laws and then hold them against you. There are states that still have common law crimes inherited from before the revolution. These are crimes that the state legislature has never defined, but are recognized by judicial custom (though it is widely agreed that even the courts in those states could not define new crimes in this way)