Those things all exist within our conscious realm. “Human brain cells in a vat used for computation” suggests horrors beyond understanding

Same reason people get scared to fly but drive everyday. Humans are simultaneously wildly irrational and terrible at calculating risk.

This is somewhat novel unlike say weapons manufacturing. Also assuming that the GP is in the tech community to some degree, it makes sense they’d have a stronger reaction.

There’s lots of bad stuff humans shouldn’t be doing.

Not sure why this is being downvoted. It’s a valid point. This neuron chip stuff is far less problematic than a lot of animal testing where you clearly have a whole organism that experiences something.

Factory farming too. The way we treat chickens in particular is out of a horror movie, and that’s in countries with some standards. Globally I’m sure many billions of animals are constantly submitted to the most grotesque torture for food.

The fear is that we don’t really understand what causes consciousness. I think that’s a valid fear, because we can’t know ahead of time whether we will inadvertently create a “person” inside the machine.

Unless your proposition is that no collection of human neurons outside of live birth can become sentient, and I’m not sure how you’d arrive at that conclusion without invoking some kind of spiritual argument.

You're equivocating two totally separate things

How is it naive? You admit that an individual neuron is a machine. 200k neurons in a petri dish isn't a brain. I'm not the naive one here.