I think it’s just a hangover from the Fane slog. Ch 4’s pretty interesting with a lot of hidden side stuff (that’s worth unhiding) once you figure out how to navigate. It’s the Abyss, that shouldn’t be easy.
I wouldn't describe it as "interesting". For example, the villain that has been hounding me for 2 whole Chapters and something like 30+ hours, while also being a key part of the whole Crusades lore, just got the dumbest, most anti-climatic, immemorable send-off you can possibly imagine. I honestly couldn't believe a team of allegedly professional writers could do something like that.
A whole bunch of new names that are supposed to be important, I guess, suddenly get dumped on you via a Wiki-like wall of text and are made the centerpiece of a a Chapter that takes place more than halfway into the game, with no prior introduction whatsoever. What the fuck is a "Hepzamirah"? Why are we getting our introduction into that supposedly main antagonist of the Chapter through nothing but a couple dozen of lines of text? Deskari at least had the decency to show up in person immediately in order to set the stage of the overall plot. One of the other biggest antagonists of the Chapter, from what I understand from spoiling myself, gets introduced as a random encounter inside a city where you have absolutely no business encountering him and he's all like "ha ha, I am now going to kidnap and experiment on you" and you're just like ".....wtf?" It feels more like the equivalent of that Bosmer wizard just dropping dead from the sky in Morrowind than an actual antagonist you're supposed to feel compelled to purse and defeat.
It's like they tried to shove an entire different game into an already existing, different game, with very little rhyme or reason. I honestly never believed I would utter the words "I miss the Crusade stuff", but here we are.