Xenoblade 3 is the first game in the trilogy that I can recommend without reservation. My 8/10 might not seem appealing to some, but I promise you that I have high praise of the game, it's just a death-by-a-thousand-cuts type of situation that drags the number down.
In fact, I truly don't want to spoil any of what Xenoblade 3 has to offer, just a few general things to know are great if you've read my other two Xenoblade reviews.
For one, the chain attack has peaked here. It was very good in 2, but it unfortunately tied to blade gacha mechanics, and Rex as the Aegis driver makes it very easy to abuse. IYKYK. In Xenoblade 3 however, you are given MUCH more to control and information in how a chain attack will play out. There is still an element of RNG, but it's far more manageable than it was in 1, and slightly more manageable than in 2. The chain attack is awesome and you will have favorite party comps.
Secondly, micromanaging is actually fun here. To not spoil too much, you are given a lot of freedom with how you want your party to look. If you're for some reason reading this without having played Xenoblade 3 yet or are looking to replay the game and didn't like it too much, I urge you to play around with a certain tool you get fairly early on. It can be kinda obtuse, so don't be afraid to look things up to get your party the way you want it.
Xenoblade 3 is great. Still plagued by things like the overworld being too big, but absolutely worth the experience in the end. Definitely one of my favorite ARPGs.

Xenoblade 2's combat makes leaps over the first game's by removing the level gap limit and improving chain attacks. This is the end of the good things I have to say about Xenoblade 2.
To address the elephant-sized breasts in the room, Xenoblade 2 is heavily marred by its tone. The story? Filled to the brim with ecchi humor where it really just isn't appropriate or funny (the infamous Mythra bed scene being a top offender). The gameplay? Dictated by a system that might as well have come straight out of a gacha game so that you can have any sort of competent team for chain attacks. The art direction? I don't even care about visuals that much but god damn, can we please put more effort in than bouncing breastily? My favorite blade design was the book girl cause she was made of books. If we're going to drive home the connection between humans and blades as different species, it would be awesome if half the blades weren't just essentially humans.
With that out of the way, the rest of the game:
Xenoblade 2's story sucks, there's no other way to put it. Rex's goal gets sidelined time and time again for other plot threads that seem to take us in an infinitely recurring circle around the central plot. Xenoblade 1 started you off with a simple goal and expanded it as the story progressed. Xenoblade 2 starts you off with a vague goal (go to Elysium because it's probably good or something maybe) and doesn't manage to meaningfully expand on it for DOZENS of hours, and by the time it does, what is it that you even care about in the world?
This isn't to say the story doesn't have its bright spots, Zeke singlehandedly carries the game's funny bone, but these moments are few and far between.
In the end, you come to realize at some point that the game doesn't have a main villain, until you remember that it DOES, he just sucks dick because his motivations are AWFUL, and that his glorified sidekick would've made for a better final boss.
And on the gameplay, outside of the chain attack and level gap, there is much to be desired. I really don't have time to get into all the micromanaging and tedium that comes with the gameplay both in and out of combat, so I'll just summarize it as needing stutter-stepping and art-recharge meals to be any fun. I wouldn't even have gone out of my way to fight special monsters in the game had I not gotten Zenobia as a blade, who's affinity chart is progressed exclusively by fighting strong monsters, a luxury I desperately wish I could say about some of the other blades I was unfortunate enough to get.

I like Xenoblade Chronicles. Xenoblade Chronicles has a good story and I like the combat.
But fuck man there's nothing to DO in this game. So much of your time is going to be spent walking around the beautiful but empty open world. Side quests and affinity are a boring slog since there is so much fetch questing involved, and even the combat (the best part of the game) is dragged down by the fact that you really can't fight monsters that are over 3 levels above you, which means that you can rarely ever challenge yourself, something the rest of the trilogy managed to solve. The chain attack is so awesome, but is dictated by RNG tied to shit that's just not fun to do.
Also I didn't play Future Connected. The chain attack is replaced by a side quest (gross), half of Shulk's monado arts are useless without vision (ew), and the story wasn't interesting enough for me to care about playing it myself (womp womp).