These people who think the controversy over the soundtrack is manufactured, or from people who didn't play it - why?
How often is there ever a controversy over a soundtrack? Almost never, right? Why would Nintendo fans suddenly choose this one to be angry about? Isn't it far more likely that massive amounts of people came to the same conclusion and said 'Wow, I really don't like this.' Argue that it's a good soundtrack all you want, but to claim that the detractors are all lying or biased is just bizarre - there's no reason they would be.
The New L.A. tracks are absolutely terrible. They probably wanted to underscore the town's "futuristic frontier town" vibe with that weird southern rock/hip hop fusion, but the tracks are just so clumsy and irritating that they just become unbearable after a few hours (after the initial shock has worn off and any subsequent attempt to find some kind of humor in them have failed).
The field tracks are better, but they are far too bombastic for their own good. It's really overbearing how the soundtrack is constantly screaming at you "LISTEN TO ME! I'M THIS GRAND, EPIC SOUNDTRACK FOR THIS GRAND, EPIC JRPG! AIN'T I AWESOME?!?" – and at full volume at that. Instead of underscoring the vistas, the music drowns them in its bombast and thus gets obnoxious very quickly as well.
They made some really baffling stylistic decisions with Xenoblade Chronicles X and it's all the more disappointing considering that they managed to strike the perfect balance with the original Xenoblade.
X is like a Xenoblade that has entered puberty: It's still visibly the same thing but it has also adopted some weird and annoying new mannerisms and, above all, very questionable tastes in fashion and music.
This is pretty much my take on it.
The entire thing is too bombastic, too tryhard, and therefore become irritating very quickly in a game that lasts 80+ hours. That's a big problem. And that applies to the field themes (which are okay as songs in a vacuum) just as much as to the vocal songs (which are indefensible). It's like a sauce in a restaurant that's interesting but so strong that it completely drowns out the flavour of the meat and veg etc. And because of the amount of vocal tracks, multiple cutscenes are completely ruined if you had subs off like I did. Yes they could have mixed the sound much better, but if Sawano hadn't plastered vocals in places where
he really shouldn't like 'touching song that will obviously play during a cutscene' then it wouldn't have happened.
Worst of all, though, was that the NLA songs began to give me a headache every time I played. It's the only game where I didn't want to turn it on because of the soundtrack, and the only game where I'd stop a play session early having got a headache because of the soundtrack. Literally has never happened before. Only other game to give me actual headaches was the first 5 hours of Metroid Prime 3 while I was getting used to the FPS pointer controls.
Needless to say, in the future when I think of my least favourite soundtracks ever, this one will come to mind alongside New Super Mario Bros for the DS before any others. I strongly disliked it.