Why is lcd screen too expensive?

Hi. İ have an apple watch series 4 with broken screen. İ watched teardown video and i think i need a new complete lcd screen. But it is very hard to find and very expensive. Almost near a new watch. İ wonder if it can be cheaper in the future? Should i wait? İs it expensive because of being a new product only? İ also wonder if anyone knows last year prices of lcd screen for apple watch s3? Was it too expensive too? İt is not as much as s4 now.

Thank you.