The less you remember, the more open is the gate for the next one like him to show up. It's for a similar reason that Germans very much do make sure the Nazis aren't forgotten about, e.g. Let him have his fame in history books.
As an example of what to avoid and how to avoid getting someone like him back.
Grüße Aus dem Heimbüro, ich habe Telko und Frühstück!
Und eine richtige Sehnsucht nach Freiheit!