Tl;DR: Layers of Fear is a psychological horror game with an intense atmosphere and emotional value. It’s less a fun game or even much of a game at all and more of an experience and work of art. Well worth 20 euro on stream[link].
So, On PC, at a 20 euro pricetag, I’ll give it a 7.65(recursive, of course) out of 10. I’d definitely recommend it if you are interested in game development at all and are ok with spending 20 on a 6.5 hour game.