What are you talking about, an entire duplicate Maori health authority was formed to prioritise the needs of Maori first, instead of New Zealanders in general.

Te Aka Whai Ora is not "an entire duplicate health authority". It's role is:

Leading change in how the entire health system understands and treats Māori health needs.
Developing strategy and policy which will create better health outcomes for Māori.
Recruiting kaupapa Māori services and other services for Māori communities.
Recruiting other services alongside Te Whatu Ora. Keeping track of the health system to make sure there are fewer inequities for Māori.

Notice this is not a duolicte of Te Whatu Ora, recieves a fraction of the funding, and is designed specifically to resolve systemic inequalities in the current health system.

Not to mention the duplicate Maori versions of other things due to co-governance, and things like Maori wards which put council seats aside just for Maori and no-one else.

Co-governance models do not have "duplicate Maori versions", they are a collaboration between Iwi and Council. Every time they have been implemented, they have resulted in improved outcomes for everyone compared to the traditional system. Co-governance already exists in a few places, and has only been beneficial.

Finally, there are no duplicate systems as you are suggesting.

We are a multicultural country with far more than two cultures, it can't be Maori vs everyone else. We need to be united as New Zealanders

Absolutely. But the current system disadvantages our indigenous population. Continuing with the system will not improve the situation, so a targeted approach is required. Better outcomes for the disadvantaged is only a good thing for society.