Finished Harold Halibut, took me ~13 hours. A visual feast, but there are several things that drag down the overall pacing of the game.
First is the amount of fetch quests or exchanges of dialogue from person A -> B -> back to A. This is present throughout the game and it is front loaded heavily in the first few hours. If you've played Pentiment, it's comparable to running back and forth between Tassing and the Abbey to varying degrees depending on the task at hand. In a vacuum, this is to be expected with the type of game it is, but things take longer than they should when they compound with other issues.
Second is the bespoke animations for various things and pathfinding for interactions. The pathfinding is more of a minor issue comparitively, but it's always present. Since Harold needs to be in a specific spot whenever he does anything besides walking/jogging, it can take an extra moment to navigate to the correct position (similar to Disco Elysium). The animations are a bigger issue for certain things (like the Tube you use to travel between locations) simply because of how often they happen and how long they take.
Third is inconsistency of some decisions. Certain tasks or conversations advance an in-game day. Some days they will simply end it for you and transition into the next day, whereas others you are made to manually travel back and sleep in your bed yourself for seemingly no reason.
I played on PC and the game froze on me twice, and I softlocked once during an interaction (which reloading fixed).
On the positive side, obviously the visuals are the star of the show. There are several characters that have their own interesting story vignettes and the narrative is suitably weird. Overall I'm glad to have experienced the game despite the flaws.