It's also somewhat misleading in the way it talks about daguerreotype decay - of course, it does happen. Witness the images in the article. BUT, the overwhelming majority of daguerreotypes are not glued to their cover glass, rather bound in a sandwich with a brass mat between the plate and the glass taped together at the edges.
It's a shame there's such damage, but at least in most cases there seems to be enough remaining image than an artist could create an lifelike rendition of the person, if these decaying images are the only reference remaining.