Stephen King’s original novel is 1,100 pages long and so there’s a lot of material there to cover, but it seems like maybe the movie focused on trying to keep too much when it should have tried to slim down.
Movie’s aren’t bad because they are long, but the longer a movie is, the better it has to manage that time.
There has to be a reason for us to follow a story for that long, and it seems that most critics will argue that IT Chapter Two doesn’t really give us one.