I don't identify my "self" (or consciousness) with memories or anything the supposed LLM in my brain might babble about. If you took those things away, I'd still be here. Rationally speaking, self is the only thing that certainly isn't an illusion. Anything you perceive could be a hallucination, memories can change or disappear, and thoughts are mere dust in the wind, but you can't have any of those things without something to perceive them. It's the only thing you know is there, whatever it is.