When you first arrive, that first act split between Kholusia and the desert? It's well-paced, it gives you a way to get acquainted with the way the new world works, the players, the factions, so-on. You move from being triumphant in your first pushback to the faerie land, which is whimsical and foreign and alien and more good stuff. Then it immediately nosedives. The primary antagonists are shown to be clueless clowns that pose no real threat to you.
You hurry off to the forest, where some weird faction barely gets developed and does functionally nothing - and a new antagonistic faction is introduced that really, really does absolutely fuckall and seems to have no point in existing. The tertiary antagonist just shows up whenever is convenient for the plot to give a monologue about the Ascians, and then you get to meet yet another fucking faction whose inner workings go completely unexplained. This faction is billed up as some isolationist warrior tribe that's managed to fend off any incursions for hundreds to thousands of years -- yet they speak the common tongue (which matters only because in the first act, the game goes through the effort to explain why you're able to use currency, understand people, and access your bank), they immediately get routed by an army that has only ever been shown to be completely incompetent, and they somehow understood their weird jungle ruins far less than some random old man did.
Then you get treated to a really really fucking forced - I mean "flashback to what just happened 5 minutes ago" forced - death fakeout, the army that you never saw doing anything is immediately routed off-screen and leaves completely to the point where it isn't menacing in the slightest or had any lasting impact, and the antagonistic nihilist-faction essentially vanishes from everyone's memory. Suffering no real long-term damage, you then go to the mandatory 'low point' of the game, which realistically should have been the bland and boring cat dying, and instead get treated to the HORROR! of a bunch of random, nameless NPCs getting killed by an easily-repelled invasion of things that still aren't that army you've heard so much about.
This genius army apparently gets distracted without any trouble, yet its general will somehow be two steps ahead of you and didn't feel like informing anyone else about what was going on. He mumbles his literal two lines of development briefly before triggering yet another fucking death fakeout that might have been mildly satisfying if it had actually happened, to cap off a great experience in a completely forgettable arc of the story in a completely forgettable and horribly-paced bit. "We've got to hurry! The army can't be distracted forever, and the Crystarium's in danger!" "lol but my wife is DEAD"
Yet again the army is routed off-screen and no-one suffers any real long-term damage or consequences, and when we launch our assault on Eulmore, we begin to learn that maybe it was because the army never existed. About eight mooks is all it takes, barging straight in the front door, against the army and a legion of mind-controlled peasants, to get to Vauthry. Why didn't we just do that from the beginning? If all the army did was lose and suffer casualties, why was it ever something to be worried about? Vauthry's character also completely changes from an autocratic despot who poses a poignant question: "If you are doomed to die, why not live out your remaining days in hedonistic bliss rather than vain struggling?" to a baby manchild with a god-complex -- which is much, much less interesting. And indeed Kholusia 2.0 is also one of the least interesting and boring fucking sections of the fucking game, which boils down to "everyone can work together!!!!!!!!!!!!!!!!" and somehow those dastardly, malicious sin-eaters we've been told to be afraid of for literally the entire game are content to just... do nothing while we kumbayah. Two characters that were charming in the first act for just being a glimpse into the world have to somehow be the CRITICAL KEYS TO EVERYTHING!!!!! in this fourth act, because because.
Vauthry gets dispatched and has nothing to say for himself except that he's a baby manchild with a god complex, confirming that the character established in the first act got binned by whoever was in charge of 3-4. We go underwater to be bored out of our fucking skulls for a little bit before we're finally plunged into Amaurot... and world-building returns, with this surreal and alien civilization having its inner-workings explained in a way that feels organic and neat, with the whole experience really, really standing out against how fucking awful everything was before it.
And acts 3/4 in this game take up an unreasonably long period of time. It's safe to say that more than half of this game's story is complete fucking trash, and nothing that gets built up in the first two acts (that isn't resolved in those acts) gets a satisfying payoff, at all. If you took out Amaurot and Emet-Selch, literally everything in the game becomes unsatisfying and uninteresting. That sure as shit ain't good writing.