What do you expect? They're just an advertisement agency. They don't have the tools or skills required to perform advanced searches in a large, unstructured data corpus.
This wasn't the reason given when the 2011 announcement was made regarding the end of the project. But since then, the archive has faced copyright issues as newspapers sign contracts with other archive services: https://www.techdirt.com/articles/20160825/10114535344/newsp...
Oh, wait.