Yes remember it is a wildlife program and some stuff is shot on covert cameras - and not all of these could be top end 4K equipment. Just getting some of these shots is amazing, let alone whether they are full 4K or not.
Planet Earth II is still a visual tour-de-force that's well worth owning on UHD.
Makes sense ... I guess my OLED really exaggerates the noise ... it's tough having a LG OLED!! ;)