No, I think that is the opposite of what makes sense. We should allow popular properties that have already provided good profits for their creators to lapse as soon as possible into the public domain, since they have the largest impact on culture, and the lowest impact on their creators' livelihoods.

Mickey Mouse is much more relevant, would lead to much more creative work, and would hurt Disney much less if it were public than making some song by some band which at best has a small dedicated following public.