Xenoblade 3 is my favourite in the series, it really is a superb game. X is definitely the best looking of the games. I love all the games in the series and only fine margins separate them.

I've been playing Xenoblade 2, Torna, and Chronicles DE over the past four years and happened to be almost done with DE by the time Xenoblade 3 was announced. I was also the reviewer of Xenoblade Chronicles 3.

IMO, Xeno 3 takes the cake. I feel the story is more interesting and emotional overall (in particular, an entire villains entire story arc which I won't spoil, but is sad and tragic), the characters really build on you and you begin to understand them better. The world is fantastically built. Though it isn't as interesting as simply being on a titan, if you've played Xeno 1 and 2 you'll understand why I think it's the best. The combat takes the best parts of both and mixes them together while adding even more flexibility. The gacha mechanic is gone, but unlocking new blade styles (the best part of Xeno 2s blade mechanic) isn't. The graphics are the best out of the series. And the QoL changes are numerous. Simple things like having on screen navigation, how easy it is to equip items best suited for your class, and even the tutorials are far more helpful.

I LOVED Xenoblade 2, but I knew it was a step down from Xeno 1. I can't say the same about Xeno 3. I can't think of a single thing that Xeno 1 does better aside from maybe the world of you don't have context from 1 and 2 before playing 3.

Regardless, IMO all of the games are top notch.

SPOILERS

First off, I'm not sure how anyone here can say X is the best game, let alone a good video game. There is so much grinding and a lack of any real narrative that it was a miserable experience. And the story that was there? Very bad. It doesn't help that the game ends on a cliffhanger for some reason. As for the grinding, consider this. Every chapter has some requirement to access it. Some of these are Heart to Heart quest which require you to have the character in your party. HOWEVER, ever story mission requires you to have the MC, Elma and Lin in your party. Furthermore, Levels don't carry across characters. So guess what, more grinding. It also doesn't help that a lot of the later chapters are "Go to X location and fight the boss." And OH BOY those "I want to eat Tatsu" jokes that happen through the whole game. They stopped being funny a few minutes after being introduced so I'm not sure why they kept them going. The only good thing about it was some of the music was great and the pollen area is amazing. 

As for the other three, they are all great. XC1 is the worst of the three mostly due to the lull in the middle of the game. Once you pass Valak Mountain, the game is downhill until the twist. It's also bad because Melia will legit sit in the back and say nothing. The later half of the game is fighting mechon in linear corridors and having Fiora complain about "her body". It's rough. I think one of the big reasons everyone loves Melia is her arch happens at one of the game's high points. The combat also falls apart past that point as there isn't enough healing in the game for the systems to work. Post game is a waste since level determines accuracy, so fighting super bosses means you are limited in building your characters.

XC2 is the best. The biggest issue with it is the VAs weren't given a lot of guidance and their voices sound off until later chapters (compare Nia and Morag in Chapter 2 and towards the end of the game). The game takes a while to get going and Chapter 4 is a slog (which sucks because it's good characterization for Tora and Poppi). But if you get past Chapter 4, it only improves towards the end. Combat is the best in all the games and gives you a ton of variety in how to play. Post game is great and New Game + gives you 7 new blades. Music is also great

XC3 (right now) seems good for it's shear about of content. However, it's pretty linear until mid way through Chapter 3. Also, after the big twist at the beginning of Chapter 6, the game feels rushed. I think this is exemplified by after beating X and Y. They just fad away. Heck, even the big dragon got a cutscene. The one saving grace is the ending is amazing and you get to see Nia and Melia. Also nice you can use them in the post game too and they have some cool quest. The main cast is great and the chemistry is outstanding. It also just does everything X was trying to do but better. 

My Ratings

2>3>1>>>>>>>>Most other videogames>>>>>>>>x

X has my favourite soundtrack of them all, so you cannot make statements like this like it is objective lol. 
They all have phenomenal soundtracks, but X really stood out to me. Got me into the composer, and made me an anime fan. Uncontrollable is one of the most epic tracks for combating unique monsters. Great for working out too.

2 is my favourite game though. X second. I am only on chapter 2 of Xenoblade 3 right now, really enjoying it. 1 was amazing. They are all amazing games. I just wish jumping on platforms was better... Makes exploring and grabbing random items on slightly elevated hills a chore sometimes.

Give us the option to turn off vocals and then the music becomes fine. Without that, you're listening to the same 1.5 verses of the song over and over again with every single battle. Tastes aside, that's bad sound design.

I played X at the same time as Rol and like him I also  recall the regional themes being good, but my recollection of the rest of the music consists of vague thoughts where generic and repetitious tend to spring to mind.

For the bonus question, yes I would like an X2 but I'm not going to hold my breath that we'll return to the planet of psychopaths again.

An aside, this thread reminded me of the enjoyment I got from the X thread that was running on here at the same time that a lot of us were playing X, being involved in that thread and the sharing of thoughts and ideas as we made our way through the game, made it feel like it was an extra part of the game play, it's a pity those type of threads seem to be rarer now.

You can’t figure out how it is that people have different tastes and opinions than you?

90 hours in of Xenoblade 3. In the middle of chapter 6. I cannot say it's my favourite until I finish it. But can already tell you guys something: Xeno 3 is giving Xeno 1 a run for its money. Something Xeno 2 and X cannot say (and trust me, I still LOVE 2 and X).

Finally finished playing XC3, so now I have completed all 4 games. Probably doesn't matter but the order I played and beat them in is: XCX, XC2, XCDE, XC3

After I beat XCDE, I couldn't really decide if I liked it more than XC2 (which after a year, I've came to the conclusion that XC2 is better than XCDE) but XC3 is definitely better than XC2. My biggest issue with XC games is that they have a really slow start and take a while to pull you in, which XC3 is the best in that regard (only takes 1-2hrs before it starts getting interesting). After you get past a certain point, the game really pulls you in till you beat it.

XC2 still has the superior soundtrack, but the improved gameplay over XC1 is trumped by XC3 that basically fuses both elements together
XC1 story is still better than XC2, but not as good as XC3
XCX... was fun when I played it

XC3 (9.8/10) > XC2 (9.5)/10 > XCDE (9/10) > XCX (5.8/10)

Bonus: Definitely would like to see a XC4 in the future, but being a continuation of this story really depends on how the DLC expansion shapes out to be.

I think I explained the issues with the game very well. It's not a good game. But let me simplify it. 3 does everything X was trying to do but far better. It also has some semblance of a story and likeable characters. The only thing X might do better is the music. If someone asked if they should play X, I would just tell them to play 3. But X is just a bad game no matter how you slice it.