In short, yes he was, but we may never know if his reasons were sound or not. Like so many other aspects of his political life, he may have done the right thing by accident.
Much has been written about this, of course, some of it eerily discombobulated in the sense that people were using it to take a shot at Turnbull while at the same time holding that Rudd was not suitable for the job. Weird.
Now, if Rudd’s claims about Turnbull’s “backflip” regarding his application for UN Sec Gen are true – if they’re true – it doesn’t reflect well on Turnbull’s character. It’s pretty piss-weak, really. Add to that the recent revelations about the Cabinet vote and quite legitimate questions arise, and have been voiced by many, regarding Turnbull’s leadership and the influence upon him by the neo-cons. As something of an aside, isn’t it interesting that “neocon” has gone out of favour and neoliberal is now the label of choice? Funny how language fads work.
Anyhoo, regardless of what you think of Rudd and his supposed fabulous intellect, for me, forgetting about him personally, the salient reason he ought not be considered is that no Australian Prime Minister of the last decade has any goddamn business wanting to be the United Nations Secretary General. Over that period this country has shown near contempt for any number of humanitarian international conventions. What sort of gall does it take to imagine that any person freely engaging in such contempt has the moral right to seek such a position?
I don’t know about you, but for me this is the real reason that Rudd ought not be a candidate. Mind you, I think it might also be said that having an ex-Prime Minister in the job might politicise it a touch too much, but that’s probably not so much of a big deal.
Your thoughts are welcome.
Left in Limbo 
Neoliberalism is about the the faith in laissez-faire capitalism that started under Pinochet dictator chip in Chile, flowing from Milton Friedman and the Chicago boys economics, you may check the documentary “The Shock Doctrine” for that:
“The Shock Doctrine: The Rise of Disaster Capitalism is a 2007 book by the Canadian author and social activist Naomi Klein. In the book, Klein argues that neoliberal free market policies (as advocated by the economist Milton Friedman) have risen to prominence in some developed countries because of a deliberate strategy of “shock therapy”. This centers on the exploitation of national crises to push through controversial policies while citizens are too emotionally and physically distracted by disasters or upheavals to mount an effective resistance. The book suggests that some man-made events, such as the Iraq War, were undertaken with the intention of pushing through such unpopular policies in their wake. Some reviewers criticized the book for making what they described as incorrect claims, while others praised it as a compelling and important work.”
Neoconservatives are about the dogs of war inside the Washington state that want to bring the ‘free world’ by force electing communism and later financing and creating Islamic terrorism as the threats to the civilized world. You may check “The power of nightmares: the rise of the politics of fear” for that:
“The film compares the rise of the neoconservative movement in the United States and the radical Islamist movement, drawing comparisons between their origins, and remarking on similarities between the two groups. More controversially, it argues that radical Islamism as a massive, sinister organisation, specifically in the form of al-Qaeda, is a myth, or noble lie, perpetuated by leaders of many countries—and particularly neoconservatives in the U.S.—in a renewed attempt to unite and inspire their people after the ultimate failure of utopian ideas.”
Neo liberalism was dead after the 2007 crisis as the previous forms of liberalism were dead after 1929 crash. That the world wasn’t able to move beyond this ideology show how it has a hold of global economy by politics.