Not sure if I'd say its THE most underrated, but I can definitely say it's probably high up there and completely understand how you feel because I absolutely enjoyed this game, loved the story, loved the characters, loved the graphics (the graphics still look better than most newer games).

Only common flaw is that it was a bit too linear, but it was a fairly new game since the release of the PS4 so i'd say devs were still testing the waters. Personally I didn't mind it as the story and combat was very engaging.

People complained that it was too short but it took me more than 8hrs to finish it, and took you 10hrs. I guess others just decided to speed run the game hitting at 4-6hrs. (But then again people like to do that with other games ie. FFXV saying its 20hrs long yet took me +50hrs long) It all depends on the player and how they player.

I wish there was a sequel in the works. I'm sure if the game had a second chance they'd definitely improve on the 'linear' and 'length of time' aspect of the game and I'm sure it'll turn out amazing.

Also, you can find this game on PSN for like $5 on sale so nobody should ever be complaining about this anymore lol