It's not just memory, the physical body also encodes trauma and stress (The Body Keeps the Score is a book that touches on this).

I would argue that if a human has absolutely zero change, mental or physical, no atom of their being is modified, then no they did not experience suffering.

I get where you're going, but the argument isn't quite right.

A LLM never has and, in their current architecture, never can/could experience suffering or real change of state.

The general and expected case for humans is that capacity. A human my indeed lose capacity, e.g. being braindead and in severe cases we do indeed say that they are not conscious or able to suffer (different argument: some would of course say that is suffering in and of itself)

This framing is a trap. It states "Dehumanize a sick patient OR concede the AI tech bro claim about LLMs"

It's also a rhetorical move I've seen several times here...