late answer by a lot but if anyone views this question, hopefully I helped.
If the silk road was never developed, china would have 2 major things different. 1: The silk road spread trade so china could have other items to use. Maybe if they didn't have x item, they couldn't have created x. 2: The silk road is what spread Buddhism. Buddhism possibly wouldn’t exist without the silk road. Those are 2 things that would change if the silk road was never developed.