"The regulators said that the controls were necessary to prevent software piracy and differentiated gaming consoles from smart phones, which legally can be jailbroken:
[T]he record demonstrated that access controls on gaming consoles protect not only the console firmware, but the video games and applications that run on the console as well. The evidence showed that video games are far more difficult and complex to produce than smartphone applications, requiring teams of developers and potential investments in the millions of dollars. While the access controls at issue might serve to further manufacturers’ business interests, they also protect highly valuable expressive works – many of which are created and owned by the manufacturers – in addition to console firmware itself.
On the plus side, the regulators re-authorized jailbreaking of mobile phones."
Source:
-) http://www.wired.com/threatlevel/2012/10/dmca-exemptions-rej...
-) http://news.ycombinator.com/item?id=4699962
I am aware that this does not fully answer your question, but this is at least their justification.