What if the mostly lost continent of "Zeelandia" had never sunk, and was still around?

https://en.wikipedia.org/wiki/Zealandia I'm just curious about this, and was wondering what the historical implications would be. What if the mostly lost continent of Zeelandia, mostly sunk for perhaps 80 million years, was still around. With a land area of close to 5 million square kilometers, right next to Australia, how would this have affected world history? This is almost 2/3 the size of Australia itself, and, thus, a full fledged "new" southern continent in the South Pacific. Surely, this would have dramatically increased the presence of human beings and human culture in this part of the world. Perhaps all of human civilization might have been affected, with much earlier vast voyages across the Pacific, and cultural cross fertilizations. One could imagine a cultural center in this part of the world that didn't develop OTL because of the social and geographical isolation. And, competition developing between this South Pacific civilization and the Northern civilizations in the East and the West. After all, this would be temperate climate, well suitable to human civilization and development. Thoughts?