Nuthatch with bald patches

Hi, I'm a fairly new bird enthusiast and have spent the past year enjoying making my garden a home for nature, and recently my partner got me a Birdfy motion camera bird feeder so I can see the birds up and close. Today I spotted a Nuthatch with some baldness on his side/underside. I have two semi-regular Nuthatches who both seem very healthy and have no visible behavioural or physical signs of distress or illness apart from this one with the bald patches.

I googled what it could be (concerned about diseases and whether I need to disinfect and retire that bird feeder for a short while) and I think it may just be from moulting (?), but another Google search suggested that Nuthatches typically moult between June/July and mid-September. Is this just a late moulting bird, a bird with mites, or is this some other issue I should be considering?

Here's the video below: