No matter, the new version is more user-friendly and beautiful. The best example is that you cannot upgrade your current Android version to any newly released Android version. Such as security purposes, and they need to maintain their continuity of product selling.
Those restrictions were created by manufacturers for some of the reasons. However, you have purchased any well-reputed Android device with paying the total amount, and you have restriction to using it. Does your Android device provide unrestricted access and device customization?