That's a very interesting view. I don't have an internal monologue and I have aphantasia. I'm very zen indeed, living in the moment and not overthinking things.

My fiancée on the other hand is pretty neurotic and has both internal monologue and can imagine things in her head. I have never wondered before whether these things are related.

Interestingly when I'm on psychedelics I do get some CEV, maybe not very vivid, but still, and while I wouldn't call it a full blown monologue, I do comment things in my head a lot when tripping.