What was the point of making pennywise so powerful

I feel like penny wise is a godlike character who can do anything against the antagonists in the show, but they nerf him so bad. How do the characters even get a chance to fight him without penny wise just killing them (considering he can make them see things). And you might say he needs them to be scared but he doesn’t. In fact he doesn’t need it at all. And if he can see the future he would know who kills him in the end and who doesn’t. This all in all confuses me and makes me think less of the it movies and shows.