This reminds me of that creepypasta about how humans evolved the uncanny valley because we once had to be afraid of human looking beings that were not human...
Huh, well that's it exactly. There's an almost innocent etherealness to it. These monsters aren't here for you, to interact with you, they're just here and this is what they look like. You don't understand their motives, or really anything about them, because they're far too other, you only perceive the similarities, and that's where the terror is. You get the sense you're seeing something secret, because if they did notice you, you feel like it would be a very different interaction.
Well put. Really nails what watching deep-sea creatures (real ones) feels like. With the added strangeness that these... look so much more familiar, in a perverse way, as if they took our likeness to better lure us...
You are correct, Jonsi (the singer) is unmistakable. He sings partially in Icelandic but mostly in like, Icelandic-sounding gibberish.
The song is Untitled #9 if you were wondering. It's a B-side from their second album
They have a pretty cool "documentary" called Heima that they filmed while touring. They play some songs in interesting places with beautiful cinematography. VERY chill. I highly recommend watching it on a weekend when you're...uh...properly motivated to chill for an hour