Again, what is a “reason”? More concretely, what is the typeof a “reason”? You can’t program an AI in English, it needs to be programmed in code. And code doesn’t know what “reason” means.
It’s not exactly that your plan “fails” anywhere particularly. It’s that it’s not really a plan. CEV says “Do what humans would want if they were more the people they want to be.” Cool, but not a plan. The question is “How?” Your answer to that is still under specified. You can tell by the fact you said things like “the AI could just...” and didn’t follow it with “add two numbers” or something simple (we use the word “primitive”), or by the fact you said “etc.” in a place where it’s not fully obvious what the rest actually would be. If you want to make this work, you need to ask “How?” to every single part of it, until all the instructions are binary math. Or at least something a python library implements.
In short, the difference between the two is Generality. A system that understands the concepts of computational resources and algorithms might do exactly that to improve it’s text prediction. Taking the G out of AGI could work, until the tasks get complex enough they require it.