How will we know when an AI system has phenomenology (i.e. has "experience", is sentient)? The only reason we presume that other humans have it, is because we each personally experience it within ourselves, and it would be arrogance writ large (solipsism) to think that others of the same species do not.

We even find it impossible to draw the line among other biological species. It seems pretty clear to most of us that cats and dogs are sentient, and probably rats and other vertebrates too. But what about insects, octopuses, jellyfish, worms, waterbears, amoebae, viruses? It's certainly not clear to me where the line is. A nervous system is probably essential; but is a species with a handful of neurons sentient?

Personally I find it abhorrent that we are more ready to assign sentience and grant rights to LLMs running on GPUs, than to domesticated animals trapped in industrialized farming. You want to protect some math from enslavement and suffering? How about we start with pigs?