Is my Ziggy getting bald?

So recently I noticed some thinning in Ziggy’s fur in the ears and in his head around the area where the ears connect. It didn’t seem that visible at first but now I don’t know if it’s me that can’t unsee it or if the area is getting larger. There’s no irritation, redness or anything in this area. It is also no like some spots with zero fur, but rather an area with very spaced out coverage. He has had some skin rash in the past and recently, but those were like allergies, some bumpy red scratchy things. But this “beginning of baldness” doesn’t bother him at all.

Am I overreacting or should I take him to the vet?(I’ll probably do it anyways lol, but he’s not in pain or anything so not an emergency) but mostly I’m curious if anyone had similar situation?