If you start with the assumption that humans have a soul, and reject the notion that machines are the same for that reason then yea what is there to discuss?

I can't disprove your faith. That's what faith is.

How would you respond to someone that thought humanoid robots had souls, but meat-based intelligence didn't? If they assumed the first, and had zero metric for how you would ever prove the second, then theyd be giving you an impossible task.

There's a point to a discussion when both sides agree on a rubric from determining fact from fiction (i.e. rooting it in empiricism) but there's no point when someone is dug in on their belief with zero method for ever changing it.

If someone could point to any actual observable difference, I will adapt my beliefs to the evidence. The reverse isn't possible, because you are starting with religious assumptions, and have don' know the difference between ideas with no rooting in physical reality and actual statements about material conditions.