Ask HN: What's stopping a hardwired AI

Simple question: can't AI exist as a "hardcoded" / coded purely using transistors and logic gates with builtin weights? (Of course from an open source model) And then just power it so every output is PHYSICALLY generated based on the input. (For example a binary added can take in information, add the bits and output with very less power consumption, can we do the same for AI?) Remove the obvious stuff like how AI isn't perfect yet ..