But is it worth it if we create more electronic waste because of it? I somewhat like the idea of the activation lock system, because it makes the devices unattractive for stealing it. On the other hand it creates more unnecessary waste (at least they way Apple implemented it).

A way to unlock them should be provided. Report the serial to apple, they try to inform the owner by mail and/or push and after a 30 days grace period it should be unlocked. Another benefit of such a system is that it might even help to locate stolen devices.