> Obviously, for this purpose, human should not have any feelings (because LLMs don't have), so can't feel pain. Or else the comparison can't work.

Other than this forcing you to ignore the overwhelming majority of humans who have functioning pain nerves:

LLMs have something functionally equivalent to pain, in this regard at least.

During training, model weights are updated depending on if the feedback was positive or negative.

It has a functional effect similar to that which pleasure and pain have with us. Not identical, so far as I know there's not been any reports of any machine learning model that is into BDSM, but for the most part functionally similar.

There is also research which has found circuits in multiple LLM models, which serve similar roles at inference time and are distinct from other emotional representations: https://arxiv.org/abs/2609.16247