I know this is a joke, but there might be an evolutionary advantage to being able to detect some light and movement when your eyes are closed.

Funnily enough I know how this would feel! I gave myself a very bad black eye during a K-hole which burst a vein above my eye causing my eye lid to swell.

It felt like having a very hot and 'sweaty' eye ball covered by a winter duvet. It was so uncomfortably hot I actually got a mini fan to blow air into my eye while I held up the swelling.

Thankfully it resolved itself but thick eye lids are not good.

I have thinner eye lids, as I have terrible eczema and as a kid they gave me skin destroyer cream for my eyes... This hit way way way to close to home:X

Ass lids? Aren't those normally called pants?

tbf we're missing another pair of eyelids, we used to have a nictatating membrane like many other animals do but nowadays that's only visible as a vestige in the corner next to the nose.

look at reptiles, when they blink there's an extra transparent eyelid that slides in from the middle corner, before the main eyelids.

granted, this wouldn't block any more light as it's transparent, but at least it protects a bit better and lets you get gunk off the eyeball more expediently

fun fact, the eyelids have the thinnest skin of the whole body