iPhone 15 Pro Max - photos have crinkly texture in closeup

In the photo above, if you look closely everything has a kind of crinkly texture, particularly in areas that should have a sandy/grainy texture. Sometimes when photographing something small, like a lizard on a rock, this crinkly look is so bad it makes the photo unusable. Has anyone else experienced this? Is there anything that can be done about it?

[Edited by Moderator]