That's one review from Steam Deck. Game just might too resource hungry and/or unoptimized for it at the moment. The user also didn't state what Proton version they used. I'm going to install it on my other Linux PC and report back later.
Edit: Works fine on my PC, running latest version of Nobara (Linux distro focused on gaming) and Nvidia drivers. I also used GE Proton 9.11 in Steam.
I had it auto-detect graphics quality (seemed to be about High settings) @ 1080p, and enabled Fur Shadows. I set DLSS to Balanced. Averaged 60-70FPS, dips down to 45ish when I entered an area with heavy rain. Played for about 15 minutes and entered the open world area after the intro. I was playing on my HTPC hooked up to an older spare TV, so I apologize for those that use 1440p or 4k since I cant test the performance at those resolutions.
My specs are:
-Ryzen 5700X
-RTX 3070 FE
-16GB DDR4 3200
-1TB nvme SSD
Edit 2: Played for another 30sh minutes, no issues. Performance did dip a bit in some open world areas, but I never saw it go below 45 FPS.
My quick review: The game has some interesting ideas, but the combat and presentation are pretty jank. Many of the early monsters just ram you like a goat, which launches you in the air and gravity is kind of floaty, so you can end up getting repeatedly tossed around. Their animations are very stiff, so sometimes it looks as though the monsters are just gliding at you versus running. The aesthetic/style of the world looks great, though. The giant tree/Ent thing stomping thru the forest was intense and surreal, I enjoyed trying to hide from it and failing.
The UI is not good, not awful. All of your important information is in the inside of your bow shaft, but it isn't presented in a clear and easily understood way. Not being able to easily tell how many arrows you have in the middle of combat is frustrating. I also think the wind direction should be easily referenced without needing to hold down a button, sort of how Ghost of Tsushima did it.
Lastly, and this is subjective, the music is not very heavy metal IMO. I was expecting something like Doom 2016, but with Cannibal Corpse, Cradle of Filth, or even Slayer type heavy metal. Instead, it's more ambient and slower; not intense at all.