Just thinking out loud: I wonder if there is a way to crowd-source correction of such metadata.
As all of us who have used Archive.org know, finding things is often a real matter of hit and miss, since so many things are put up with either wrong or horribly incomplete data. Moreover, one of the first things I noticed in the Canadian data is that there seem to be cases where all the diacritical letters in a title have either disappeared, or simply do not appear on screen -- I didn't do any systematic sort of survey. But the resources are wonderful and often really crucial for us, most especially in this lockdown situation, so it would be a positive thing if there were a way to make the resource better.
(Another) Jonathan