When Canon did this, the signing key was the same for every camera of the same model, and you could extract it by running code on the camera. I don't have faith in camera companies implementing this properly.
Hence the “if”. The technology exists, and is for example in widespread use in smart cards, smartphones, and laptops. The article you link to is also from 2010, so the Canon development is probably 15 years old or more. I would expect a better level of security awareness by now.
https://web.archive.org/web/20120125045005/http://www.elcoms...