According to you, number 2 in a World cup tournament is nothing special which I completely disagree with. Anyone who underestimates New Zealand are fooling themselves especially with their current lineup.
I am not judging anything here, i just said the facts, a causal fan might not know nor care about looking at who all played in the world cup finals, but they might know who all won the world cup till now, that is not the case with cricket alone, just take any major sporting events, no one remembers who came second and third, take athletics, football, tennis, just try to remember all the final matches you have seen or in the past, i bet you wont remember everything, but you might know who became the champion.
South Africa will always be a formidable side to beat no matter how many times they choke or lose. Australia will always be the team to beat, but the current team is nowhere as amazing as the previous Australian lineups.
You really do not need the best team always to win matches, when it comes to a world tournament like world cup, if you can perform to the best for 8 matches you are the champion and Australia have done that many times consistently and so is the reason they were champions more than any other country.
I will site examples for you, when India won in 1983, they did not have the best team but they performed really well when it mattered and hats off to Kapil for his 175 when they were down for 17 for 5 something like that, it was a collective effort and that is how they won the world cup, in 1992 Pakistan was not the best team and they lost to India but under Imran Khan they played as an unit after those defeats and won the world cup, in 1996 world cup Srilanka came up with the tactics to open with Jayasurya and Romesh Kaluwitharana both explosive players and Aravinda de Silva to stablize the innings if they loose early wickets and they carried out that game play and won the tournament defeating Australia in the final.