We just went this weekend. They had some pathways blocked off, and some parts of the studio tour had Halloween stuff kind of blocking the stages, but nothing of major annoyance. We didn't find any of the decorations to be too much, but my youngest is 10, so I don't have any little ones.
The Jurassic World ride coming in 2019 means the old version closed, but that had nothing to do with HHN. A couple of things went down for short periods of time, but nothing was closed this weekend. I think you must have just caught a temporary closure when something malfunctioned.