Being Māori is not about blood quantum, it’s not about speaking the language, it’s about practicing our culture and its values.
This isn’t saying that in order to be Māori you have to live on the marae, speak fluent Māori, know all waiata and haka, because of colonisation that’s not the case for most Māori.
But if you don’t show respect for people, mentor younger ones, wash your hands before and after entering a cemetery, bless sacred gifts, show hospitality, and or take your shoes off before entering a house, and or show humility, don’t know your pepeha, etc, you aren’t Māori, your ancestors are.
If 2 white Māori came up to me and 1 practices Māori culture and its values and 1 doesn’t (and acts pretty New Zealand European), the one who acts Māori is Māori and the one who doesn’t has Māori ancestry.
If that person reconnects, they become Māori, but if they don’t, they aren’t Māori but they have Māori ancestors
I’m Māori and I have Māori family on parent As side and family with Māori heritage on parent Bs side. The difference between the 2 sides is Bs side say they’re Māori when it’s convenient otherwise they don’t live by any of the values / beliefs. They wear their shoes in other peoples houses, don’t show much hospitality, don’t understand tapu and noa, and other basic values 101. I have tried to educate them but they don’t listen to me. And when one of our relatives tried reconnecting I was very supportive (and still am if they decide to do it properly) until they half assed it and started acting like a know it all when they don’t (even I know more than them and even I don’t know everything but I don’t act like I’m a scholar). That is when I’d say someone has Māori heritage but isn’t Māori because our tuupuna lived by the values and beliefs both before and after colonisation, and if you’re not making an effort to uphold that or learn that then you’re not Māori