The CGI kind of killed it. Most of the "scary" parts of the movie were unrealistic CGI zombies that were laughable. The only scary parts were the small amount of times they allowed Bill Skarsgård to perform. They should of done more focus on Pennywise and his acting because he carried the horror of the movie. The rest of it, I couldn't take seriously because of the bad CGI.
Even the ending of defeating IT by not being scared of him was identical to the ending of Chapter 1. It took them the whole movie to come to the same conclusion as the first movie. And that plot point doesn't match up to all the children that died even when they weren't afraid, such as the little girl underneath the bleachers.