Let me preface this by saying this is just my highly unprofessional opinion.
Let me follow this up by suggesting to not-watch this season, or if possible, don't watch the series in its entirety. The manga might be fine, I dno.
Now for the slightly more in-depth reasons why:
While watching, I felt like I missed entire episodes in-between episodes. Episodes felt jumbled and disconnected. I had no idea what was going on or why. Characters kept spouting cool-sounding but nonsensical one-liners. Motivations were questionable at best. There was no drive or end goal to look forward to. Most episodes were me wondering what was going on, and cringing at the ridiculousness of it all.
To give one specific example, at one point the ghouls go raid a prison. But it's never explained why or how; they just do. They free a bunch of mooks with wildly varying powers. A whole bunch of new characters are introduced and instantly discarded. At the end, it's like it never happened, except that Kanaki is now randomly more crazy than before, having thrown away his entire personality and what little bit there was to like.
Art & sound
Fine, no complaints there. I don't think the songs were as good as the first season, but still fine. Art looked fine to me, and animation was find where it mattered.
Second big problem; there are a hundred-and-one characters who appear once, are a big deal apparently, then are never mentioned or seen again. Side characters are bumbling along fighting for screentime, and sure enough they get a bit more, but it doesn't really develop them any better. There are several character interactions that came out of nowhere, and lead nowhere. There was a random character background scene that, while cool, added nothing. Worst of all, Kaneki.. He went from a monotone pacifist to a whiny edgelord. I guess he's insane after what happened in season 1, but it kinda takes away any premise he had as a character.
Due to the crazy nonsensical plot (or lack thereof), I literally couldn't watch anymore after 8 episodes. Even before then, it was a drag, forcing myself to put on another episode, hoping it'd be better than the last.