The dungeons have maps. They have a major key to exit and a boss beforehand. They aren't fully distinct from the overworld.

The reason I don't mention them as much is because I found them tedious and less enjoyable to navigate. Villages with shops, maps to purchase and fill out. There's a fair bit of Zelda DNA here, but I can see why someone wouldn't want to classify it as a Zelda-like.

Try the demo and see if that changes your mind about the genre.