I wouldn't go that far
it is R*'s best game to date imo, and the only one of their games I got to 100%, but a lot of that is spent picking flowers and slaughtering cute furry animals, it does suffer from the same repetitive task syndrome as in all their games.
The story isn't bad at all but if that's all you do there isn't a lot of it, the world they created is vast and believable, it's easy to waste hours just wandering around.
my main gripes were some of the voice acting and too many missions revisiting the same locations, the world is huge but there's not much in it, the combat cover system is better but still a little clunky.