That doesn't mean that it's easy, it just means that hacking a PS3 is highly motivating. Making some lame centerfuge explode half-way around the world is high on patriotism (I guess) but short on lols.
Of course the other evidence strongly suggests that this group is NSA-employed, but the real reason why their malware is so much more sophisticated than anything else out there isn't that nation states have staggering amounts of resources, it's simply that normal malware doesn't need to be sophisticated.