It seems a shame that the attribution wasn't developed with the flickr image search in the editor (as a gesture of academic integrity if not required in Public Domain).
If Attribution was added to the the development a much larger range of images would be available to use from the FlickrCC repository (CC By).
Can a tool with broader functionality be developed along the lines of FlickrCC in Canvas? One that includes wikimedia Commons might be good. Or one that does more than search for images even? Perhaps something like theCC Search
At the very least, I think Attribution to source in the existing Flickr function needs to be added, to aid better discipline around academic integrity, even for 'Public Domain' images.
There is no assurance that an image in Flickr has the copyright status it claims to have. Anyone can upload any image with any copyright notice, including Public Domain and there is no internal process to verify that. Youtube has automatic checks followed by procedures involving people for example. Wikimedia Commons has vast numbers of volunteers who check all content. Flickr does not. Adding an Attribution will help some people check this, such as librarians tasked with checking a course for its copyright and academic integrity.