Have you seen the game? Just because it's pixel art does not mean it's easy to make. Especially pixel art as highly detailed as this. Not even the critically acclaimed Celeste has pixel art as well made as this. Most indie games don't. I haven't played Owlboy, so I don't know how great it is from my personal view, but reviews suggest it's a great game. I don't understand this meme that just because it isn't a 3D game made with an AAA budget that it's worthless. Owlboy seems to be better than many AAA 3D games.
If sidescrollers aren't your cup of tea or you're not a fan of ~16-bit art, fine, but saying that a well-made game should just be capped at some low price range, while at the same time being perfectly fine with games with other aesthetics costing more is bizarre to say the least.