Not sure I agree, but accept it's not my area of expertise. We don't necessarily want to simulate the human brain the way it does actually function biologically, rather simulate the its most useful behaviors, which are hard to see as being intrinsically linked to the workings of the gut.

There's an imperfect truth to the comment you're replying to.

You're right that it's unnecessary to emulate the brain down to its finest implementation details, down to the molecule or even down to the cell.

However, I contend that it's essentially impossible to create a "relatable AI" (an AI that behaves and thinks like humans do) without proper consideration of embodiment. A large part of why the brain works the way it does, at a macro level, emerges from the vehicle it's in, and broadly speaking both its afferents/inputs and efferents/outputs.