I thought FF13 was middle of the road for the series. Really liked some elements of it, really disliked others.
I don't think it was out of place for the series. Take a bit of FF7, a bit of FF8, and a bit of FF10, put them in a blender, and you get the general tone and aesthetic of 13. Yeah, it was linear, but linear isn't by any means a killer for me. I actually liked the game a lot LESS by the time it opened up. The characters went from flawed and angry to loveable smiling gormless idiots, and the plot got pretty impenetrable. The battle system was both too hard and too boring, a truly impossible combination, and the backstory being almost entirely delivered via ingame encyclopedia is the most fucking lazy storytelling crutch in existence. But I really, really liked some of the characters, it was beautiful, the dialogue was well written, the plot totally had me captivated up until the third act at least, and it has a truly beautiful and well executed ending, even if I can only about half tell what's going on. I give it a solid C+/B- on the whole. Not too shabby.
I think people don't really know what they want from a Final Fantasy game. Square makes FF12, an open world, maturely written extravaganza, and everyone complains that it's too big and open and the characters are bland and the story is too political and not epic enough. So Square makes FF13, a linear, limited affair with characters painted in broad strokes and story much more conventional for a JRPG, and everyone complains that it's too small and closed and the characters are too whackey and the story is too sprawling.
Frankly, I think everyone just wants Square to make a Final Fantasy that makes them feel the way that FF4/6/7/8/9/10 made them feel when they played it for the first time. Except they're never going to get that, because they're not 15 anymore.
Also, comparing JRPGs to WRPGs is like comparing racing games to Grand Theft Auto. Yeah, there's a VAGUE correlation and similarity of genre, but when you're playing a racing game, you want closed tracks where you drive really fast and beat the other dudes who are driving really fast. When you play GTA you want a big world where you drive anywhere and run people over and carpet bomb police stations from helicopters. It's a different itch. I love CRPGs , I love JRPGs, I would be pissed if Mass Effect got a turn based battle system with animu character tropes, just like I'd be pissed if Final Fantasy got a player-defined narrative with an open world. Open is not better than linear. It's just different.