Personally - and i do mean this wholeheartedly, I dont speak for the sake of shitting on the game - I do think the bad rep its got its very well deserved. Its one of those games popularly rejected by the fans that do make me feel the fans have it right a couple of times.
I think its one of the weakest entries in the franchise (next to FF2, who a lot of people apparently havent played) and I do think the stronger attributes in most FF games - meaning, story, characters and world building - fall flat in this one, and in a major way. Gameplay wise is unremarkable, I didnt particularly like the battle system, I think its the only FF game I can think as of a right now that if your controlled character dies, the game ends. Weird. I absolutely loathe the Paradigm system as a mean to character upgrading. And it being linear for the most part did harm the experience - for me at least. If some of the areas of the game had an exploration aspect to it, like Gran Pulse did, I think it would've helped a bit.
I dont think its a bad game - as a stand alone game - It has some enjoyable aspects to it, specially music and visuals, which are superb - but its hard for me to enjoy it as a FF game.