It started automatically with a system update, and I didn’t realise for ages. Mostly it’s fine, I think it is more if you are taking a long-distance photo and then you zoom in, and AI helpfully fills in the extra pixels for you to make it look like a bird or whatever.
I don’t remember now what I did to check and then disable the AI assistance, but to be honest, it doesn’t seem to have made any difference anyway. I have a point-and-shoot instead now for iNat stuff.