How many times have you clicked a link and found the page 404 or redirect you somewhere else? That is the real value of the web archive to me. Wikipedia uses it a lot as well, they automatically snapshot any link used as a reference and if the page goes away they automatically swap the link for a web archive version.

Reading a reference 50 or even 200 years old is not absurd. A post detailing some research findings which is referenced in wikipedia is still greatly valuable. Youtube historians often reference ancient patents to uncover the history of old items.