I don't see how the analogy applies.

What if we were able to make a an exact copy of a human brain, and the behavior was indistinguishable from a "naturally formed" human? Would that still be like a flight simulator vs actual flight?

I think a better analogy is a natural diamond vs an artificial one. Or for that matter an artificial heart. Is an artificial heart vs a natural heart like a flight simulator compared to actual flight?

Making a copy of a brain is equivalent to making a copy of a plane - if you can fly in that copy it’s not a simulator, it’s a real thing.

At some point while building better and better flight simulators we might end up building an actual plane. Same can happen when simulating emotions or intelligence.

All this makes sense without involving Cartesian dualism.

Well, sorry, but I think your analogy is a stretch. A flight simulator is simulated flight. An airplane is artificial flight. A bird is natural flight. Is the airplane closer to the bird or the flight simulator?

And what about the word "flight"? Most people think airplanes fly, even though they are not autonomous entities, and they don't flap their wings like birds or insects or bats. But is it really flight?

Ok, you probably think yes, of course it is. Then what about submarines? Do they swim? If not, why not?

(yes I am referencing Edsger Dijkstra's famous quote that is relevant here: "The question of whether machines can think is about as relevant as the question of whether submarines can swim.")

You’re the one who’s stretching the analogy. Just like there’s no need to introduce dualism, there’s no need to introduce different kinds of a flight. For the purposes of this discussion, flight is what’s being simulated by the flight simulator, just like emotions is what those robots are trying to simulate. I don’t see how that’s different in principle.

Maybe currently it's more like a stuffed toy parrots vs. a real parrot. It may look similar but the underlying mechanism is missing.

Whereas when robots get advanced enough, it'll be the difference between a model plane and a parrot. They both fly, even if they achieve it slightly differently.